feat(coding-agent): add prompt cache miss tracking (#6427)

Detect prompt cache misses per turn by comparing each assistant message's
cache reads against the previous request's prompt tokens (core/cache-stats.ts).
Significant misses emit a warning-colored transcript notice at the turn they
occur, noting idle gaps past the cache TTL and model switches when relevant.

/session gained cache statistics: a compact token/cache breakdown with hit
rate, a $-prefixed cost section with per-model cost breakdown, and the
cumulative cost re-billed due to cache misses.

.github/APPROVED_CONTRIBUTORS

@@ -243,3 +243,23 @@ Mearman pr
 dodiego pr
 
 any-victor pr
+
+geraschenko pr
+
+skhoroshavin pr
+
+cyzlmh pr
+
+xz-dev pr
+
+rajp152k pr
+
+affanali2k3 pr
+
+ArcadiaLin pr
+
+anilgulecha pr
+
+DeviosLang pr
+
+HarrodRen pr

.github/workflows/build-binaries.yml

@@ -17,11 +17,17 @@ on:
 
 permissions: {}
 
+concurrency:
+  group: build-binaries-${{ github.event.inputs.tag || github.ref_name }}
+  cancel-in-progress: false
+
 jobs:
+  # Keep the public GitHub Release publication last. Binary assets are staged in
+  # a draft release first; cleanup removes the draft if later publishing fails.
   build:
     runs-on: ubuntu-latest
     permissions:
-      contents: write
+      contents: read
     env:
       RELEASE_TAG: ${{ github.event.inputs.tag || github.ref_name }}
       SOURCE_REF: ${{ github.event.inputs.source_ref || github.event.inputs.tag || github.ref_name }}
@@ -46,18 +52,105 @@ jobs:
       - name: Build binaries
         run: ./scripts/build-binaries.sh
 
-      - name: Extract changelog for this version
-        id: changelog
+      - name: Prepare GitHub release payload
         run: |
+          set -euo pipefail
+
+          mkdir -p release-assets
+
           VERSION="${RELEASE_TAG}"
           VERSION="${VERSION#v}"  # Remove 'v' prefix
-          node scripts/release-notes.mjs extract --version "${VERSION}" --tag "${RELEASE_TAG}" --out /tmp/release-notes.md
+          node scripts/release-notes.mjs extract --version "${VERSION}" --tag "${RELEASE_TAG}" --out release-assets/RELEASE_NOTES.md
+          node scripts/generate-coding-agent-install-lock.mjs --check
+          cp packages/coding-agent/install-lock/package.json release-assets/pi-coding-agent-install-package.json
+          cp packages/coding-agent/install-lock/package-lock.json release-assets/pi-coding-agent-install-package-lock.json
 
-      - name: Create GitHub Release and upload binaries
+          cd packages/coding-agent/binaries
+
+          binary_assets=(
+            pi-darwin-arm64.tar.gz
+            pi-darwin-x64.tar.gz
+            pi-linux-x64.tar.gz
+            pi-linux-arm64.tar.gz
+            pi-windows-x64.zip
+            pi-windows-arm64.zip
+          )
+
+          for asset in "${binary_assets[@]}"; do
+            test -f "${asset}"
+          done
+
+          cp "${binary_assets[@]}" "${GITHUB_WORKSPACE}/release-assets/"
+
+          cd "${GITHUB_WORKSPACE}/release-assets"
+          release_assets=(
+            pi-darwin-arm64.tar.gz
+            pi-darwin-x64.tar.gz
+            pi-linux-x64.tar.gz
+            pi-linux-arm64.tar.gz
+            pi-windows-x64.zip
+            pi-windows-arm64.zip
+            pi-coding-agent-install-package.json
+            pi-coding-agent-install-package-lock.json
+          )
+          sha256sum "${release_assets[@]}" > SHA256SUMS
+
+      - name: Upload GitHub release payload
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: release-assets-${{ env.RELEASE_TAG }}
+          path: release-assets/*
+          if-no-files-found: error
+          retention-days: 14
+
+  stage-github-release:
+    runs-on: ubuntu-latest
+    needs: build
+    permissions:
+      actions: read
+      contents: write
+    env:
+      GH_REPO: ${{ github.repository }}
+      RELEASE_TAG: ${{ github.event.inputs.tag || github.ref_name }}
+    steps:
+      - name: Download GitHub release payload
+        uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
+        with:
+          name: release-assets-${{ env.RELEASE_TAG }}
+          path: release-assets
+
+      - name: Validate GitHub release payload
+        run: |
+          set -euo pipefail
+
+          cd release-assets
+
+          expected_assets=(
+            pi-darwin-arm64.tar.gz
+            pi-darwin-x64.tar.gz
+            pi-linux-x64.tar.gz
+            pi-linux-arm64.tar.gz
+            pi-windows-x64.zip
+            pi-windows-arm64.zip
+            pi-coding-agent-install-package.json
+            pi-coding-agent-install-package-lock.json
+            SHA256SUMS
+            RELEASE_NOTES.md
+          )
+
+          for asset in "${expected_assets[@]}"; do
+            test -f "${asset}"
+          done
+
+          sha256sum -c SHA256SUMS
+
+      - name: Create draft GitHub Release and upload binaries
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
-          cd packages/coding-agent/binaries
+          set -euo pipefail
+
+          cd release-assets
 
           release_assets=(
             pi-darwin-arm64.tar.gz
@@ -66,25 +159,39 @@ jobs:
             pi-linux-arm64.tar.gz
             pi-windows-x64.zip
             pi-windows-arm64.zip
+            pi-coding-agent-install-package.json
+            pi-coding-agent-install-package-lock.json
+            SHA256SUMS
           )
-          sha256sum "${release_assets[@]}" > SHA256SUMS
-          release_assets+=(SHA256SUMS)
 
-          if gh release view "${RELEASE_TAG}" >/dev/null 2>&1; then
-            gh release edit "${RELEASE_TAG}" \
-              --title "${RELEASE_TAG}" \
-              --notes-file /tmp/release-notes.md
-            gh release upload "${RELEASE_TAG}" "${release_assets[@]}" --clobber
-          else
-            gh release create "${RELEASE_TAG}" \
-              --title "${RELEASE_TAG}" \
-              --notes-file /tmp/release-notes.md \
-              "${release_assets[@]}"
+          existing_release="$(gh release view "${RELEASE_TAG}" --json isDraft --jq .isDraft 2>/dev/null || true)"
+          if [[ "${existing_release}" == "false" ]]; then
+            echo "::error::GitHub Release ${RELEASE_TAG} is already published. Refusing to mutate a public release."
+            exit 1
+          fi
+          if [[ "${existing_release}" == "true" ]]; then
+            gh release delete "${RELEASE_TAG}" --yes
+          fi
+
+          gh release create "${RELEASE_TAG}" \
+            --verify-tag \
+            --draft \
+            --title "${RELEASE_TAG}" \
+            --notes-file RELEASE_NOTES.md \
+            "${release_assets[@]}"
+
+          expected_asset_names="$(printf '%s\n' "${release_assets[@]}" | sort)"
+          actual_asset_names="$(gh release view "${RELEASE_TAG}" --json assets --jq '.assets[].name' | sort)"
+
+          if [[ "${actual_asset_names}" != "${expected_asset_names}" ]]; then
+            echo "::error::Draft GitHub Release asset set does not match expected files."
+            diff -u <(printf '%s\n' "${expected_asset_names}") <(printf '%s\n' "${actual_asset_names}") || true
+            exit 1
           fi
 
   publish-npm:
     runs-on: ubuntu-latest
-    needs: build
+    needs: stage-github-release
     environment: npm-publish
     permissions:
       contents: read
@@ -124,9 +231,6 @@ jobs:
       - name: Test
         run: npm test
 
-      - name: Verify release artifacts are committed
-        run: git diff --exit-code
-
       - name: Upgrade npm for trusted publishing
         run: |
           npm install -g npm@11.16.0 --ignore-scripts
@@ -134,3 +238,57 @@ jobs:
 
       - name: Publish npm packages
         run: node scripts/publish.mjs
+
+  publish-github-release:
+    runs-on: ubuntu-latest
+    needs:
+      - stage-github-release
+      - publish-npm
+    permissions:
+      contents: write
+    env:
+      GH_REPO: ${{ github.repository }}
+      RELEASE_TAG: ${{ github.event.inputs.tag || github.ref_name }}
+    steps:
+      - name: Publish staged GitHub Release
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          set -euo pipefail
+
+          existing_release="$(gh release view "${RELEASE_TAG}" --json isDraft --jq .isDraft 2>/dev/null || true)"
+          if [[ "${existing_release}" == "" ]]; then
+            echo "::error::Draft GitHub Release ${RELEASE_TAG} does not exist."
+            exit 1
+          fi
+          if [[ "${existing_release}" == "false" ]]; then
+            echo "::error::GitHub Release ${RELEASE_TAG} is already published."
+            exit 1
+          fi
+
+          gh release edit "${RELEASE_TAG}" --draft=false
+
+  cleanup-draft-github-release:
+    runs-on: ubuntu-latest
+    needs:
+      - build
+      - stage-github-release
+      - publish-npm
+      - publish-github-release
+    if: ${{ always() && needs.stage-github-release.result != 'skipped' && (needs.stage-github-release.result != 'success' || needs.publish-npm.result != 'success' || needs.publish-github-release.result != 'success') }}
+    permissions:
+      contents: write
+    env:
+      GH_REPO: ${{ github.repository }}
+      RELEASE_TAG: ${{ github.event.inputs.tag || github.ref_name }}
+    steps:
+      - name: Delete draft GitHub Release after failure
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          set -euo pipefail
+
+          existing_release="$(gh release view "${RELEASE_TAG}" --json isDraft --jq .isDraft 2>/dev/null || true)"
+          if [[ "${existing_release}" == "true" ]]; then
+            gh release delete "${RELEASE_TAG}" --yes
+          fi

.github/workflows/issue-analysis.yml

@@ -0,0 +1,634 @@
+# Runs the repo's /is prompt against an issue when the `pi-analyze` label is added
+# or when a staff member comments `@issuron analyze` anywhere on an issue.
+#
+# Comment triggers can include one `#run-on-*` tag anywhere in the text:
+#   @issuron analyze #run-on-linux    -> ubuntu-latest (default)
+#   @issuron analyze #run-on-windows  -> windows-latest
+#   @issuron analyze #run-on-mac      -> macos-latest
+#
+# Label triggers always run on the default Linux runner. Runner selection is
+# intentionally restricted to hardcoded aliases in the authorization step.
+#
+# Setup required before this works:
+#   1. Create a `pi-analyze` GitHub environment on the repo and add a
+#      `PI_AUTH_JSON` secret containing the contents of a pi auth.json
+#      (~/.pi/agent/auth.json).
+#   2. Create the `pi-analyze` label.
+#   3. Add a repository secret `EARENDIL_ORG_READ_TOKEN` with permission to
+#      read `earendil-works` org membership. The authorization job uses it to
+#      verify that the label actor is an active member of `earendil-works/staff`.
+#   4. Add an environment secret `PI_GIST_TOKEN` on `pi-analyze` with gist
+#      creation permission. The analysis job uses it to upload the exported
+#      session gist.
+#   5. Add an environment secret `PI_AUTH_UPDATE_TOKEN` on `pi-analyze` with
+#      permission to update this repo's environment secrets. The analysis job
+#      uses it to write back refreshed `PI_AUTH_JSON` contents.
+#
+# The selected runner must have Node.js support plus gh, fd, and ripgrep. GitHub
+# hosted runners are bootstrapped below; future self-hosted aliases should have
+# those dependencies preinstalled or installable by the setup steps.
+#
+# The session runs in a high-entropy checkout directory so the recorded cwd is
+# a unique string. Import the session into a local checkout with the
+# /ir extension command (.pi/extensions/import-repro.ts):
+#   pi "/ir <gist-id | gist-url | pi.dev/session URL>"
+
+name: Issue Analysis
+
+on:
+  issues:
+    types: [labeled]
+  issue_comment:
+    types: [created]
+
+permissions:
+  contents: read
+  issues: write
+
+concurrency:
+  group: issue-analysis-${{ github.event.issue.number }}
+  cancel-in-progress: false
+
+jobs:
+  authorize:
+    runs-on: ubuntu-latest
+    outputs:
+      should_run: ${{ steps.verify.outputs.should_run }}
+      extra_instructions: ${{ steps.verify.outputs.extra_instructions }}
+      runs_on: ${{ steps.verify.outputs.runs_on }}
+      runner_os: ${{ steps.verify.outputs.runner_os }}
+      runner_profile: ${{ steps.verify.outputs.runner_profile }}
+    steps:
+      - name: Verify sender permission
+        id: verify
+        uses: actions/github-script@v7
+        env:
+          ORG_READ_TOKEN: ${{ secrets.EARENDIL_ORG_READ_TOKEN }}
+        with:
+          script: |
+            const ANALYZE_LABEL = 'pi-analyze';
+            const TRIGGER_RE = /@issuron\s+analyze\b/i;
+            const RUN_ON_TAG_RE = /#run-on-([a-z0-9][a-z0-9_-]*)\b/gi;
+            const RUNNER_PROFILES = {
+              linux: { runsOn: 'ubuntu-latest', os: 'linux' },
+              windows: { runsOn: 'windows-latest', os: 'windows' },
+              mac: { runsOn: 'macos-latest', os: 'macos' },
+            };
+            const RUN_ON_ALIASES = {
+              linux: 'linux',
+              ubuntu: 'linux',
+              'ubuntu-latest': 'linux',
+              windows: 'windows',
+              win: 'windows',
+              'windows-latest': 'windows',
+              mac: 'mac',
+              macos: 'mac',
+              darwin: 'mac',
+              'macos-latest': 'mac',
+            };
+
+            const username = context.payload.sender.login;
+            let extraInstructions = '';
+            let runnerProfile = 'linux';
+
+            core.setOutput('should_run', 'false');
+            core.setOutput('extra_instructions', '');
+            core.setOutput('runs_on', JSON.stringify(RUNNER_PROFILES.linux.runsOn));
+            core.setOutput('runner_os', RUNNER_PROFILES.linux.os);
+            core.setOutput('runner_profile', runnerProfile);
+
+            if (context.eventName === 'issues') {
+              if (context.payload.action !== 'labeled' || context.payload.label?.name !== ANALYZE_LABEL) {
+                console.log('Not a pi-analyze label event');
+                return;
+              }
+            } else if (context.eventName === 'issue_comment') {
+              if (context.payload.issue.pull_request) {
+                console.log('Ignoring pull request comment');
+                return;
+              }
+              const body = context.payload.comment.body || '';
+              if (!TRIGGER_RE.test(body)) {
+                console.log('Comment does not contain an @issuron analyze trigger');
+                return;
+              }
+
+              const resolvedProfiles = new Set();
+              const unknownTags = [];
+              for (const match of body.matchAll(RUN_ON_TAG_RE)) {
+                const tag = match[1].toLowerCase();
+                const resolved = RUN_ON_ALIASES[tag];
+                if (!resolved) {
+                  unknownTags.push(tag);
+                } else {
+                  resolvedProfiles.add(resolved);
+                }
+              }
+
+              if (unknownTags.length > 0) {
+                core.setFailed(`Unknown issue analysis runner tag(s): ${unknownTags.map((tag) => `#run-on-${tag}`).join(', ')}`);
+                return;
+              }
+              if (resolvedProfiles.size > 1) {
+                core.setFailed(
+                  `Conflicting issue analysis runner tags: ${Array.from(resolvedProfiles)
+                    .map((profile) => `#run-on-${profile}`)
+                    .join(', ')}`,
+                );
+                return;
+              }
+
+              runnerProfile = Array.from(resolvedProfiles)[0] || 'linux';
+              extraInstructions = body.replace(TRIGGER_RE, ' ').replace(RUN_ON_TAG_RE, ' ').trim();
+            } else {
+              console.log(`Unsupported event: ${context.eventName}`);
+              return;
+            }
+
+            async function removeTriggerLabel() {
+              if (context.eventName !== 'issues') return;
+              try {
+                await github.rest.issues.removeLabel({
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  issue_number: context.issue.number,
+                  name: ANALYZE_LABEL,
+                });
+              } catch (error) {
+                if (error.status !== 404) throw error;
+              }
+            }
+
+            if (!process.env.ORG_READ_TOKEN) {
+              await removeTriggerLabel();
+              core.setFailed('EARENDIL_ORG_READ_TOKEN is not configured; refusing to run issue analysis.');
+              return;
+            }
+
+            try {
+              const response = await fetch(
+                `https://api.github.com/orgs/earendil-works/teams/staff/memberships/${encodeURIComponent(username)}`,
+                {
+                  headers: {
+                    Accept: 'application/vnd.github+json',
+                    Authorization: `Bearer ${process.env.ORG_READ_TOKEN}`,
+                    'X-GitHub-Api-Version': '2022-11-28',
+                  },
+                },
+              );
+
+              if (response.status === 404) {
+                await removeTriggerLabel();
+                core.setFailed(`@${username} is not an active earendil-works/staff member.`);
+                return;
+              }
+
+              if (!response.ok) {
+                const body = await response.text();
+                await removeTriggerLabel();
+                core.setFailed(
+                  `Could not verify earendil-works/staff membership for @${username}: HTTP ${response.status} ${body}`,
+                );
+                return;
+              }
+
+              const membership = await response.json();
+              if (membership.state !== 'active') {
+                await removeTriggerLabel();
+                core.setFailed(`@${username} is not an active earendil-works/staff member.`);
+                return;
+              }
+              console.log(`earendil-works/staff membership for @${username}: ${membership.state}`);
+            } catch (error) {
+              await removeTriggerLabel();
+              core.setFailed(
+                `Could not verify earendil-works/staff membership for @${username}: ${
+                  error instanceof Error ? error.message : String(error)
+                }`,
+              );
+              return;
+            }
+
+            const { data } = await github.rest.repos.getCollaboratorPermissionLevel({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              username,
+            });
+            if (!['admin', 'write'].includes(data.permission)) {
+              await removeTriggerLabel();
+              core.setFailed(
+                `@${username} has '${data.permission}' permission; write or admin is required to trigger issue analysis.`,
+              );
+              return;
+            }
+
+            if (context.eventName === 'issue_comment') {
+              await github.rest.issues.addLabels({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                labels: [ANALYZE_LABEL],
+              });
+            }
+
+            const profile = RUNNER_PROFILES[runnerProfile];
+            console.log(`Selected issue analysis runner profile: ${runnerProfile} (${JSON.stringify(profile.runsOn)})`);
+            core.setOutput('should_run', 'true');
+            core.setOutput('extra_instructions', extraInstructions);
+            core.setOutput('runs_on', JSON.stringify(profile.runsOn));
+            core.setOutput('runner_os', profile.os);
+            core.setOutput('runner_profile', runnerProfile);
+
+  analyze:
+    needs: authorize
+    if: needs.authorize.outputs.should_run == 'true'
+    runs-on: ${{ fromJSON(needs.authorize.outputs.runs_on) }}
+    environment: pi-analyze
+    timeout-minutes: 45
+    concurrency:
+      group: issue-analysis-pi-auth
+      cancel-in-progress: false
+    env:
+      ISSUE_ANALYSIS_MODEL: openai-codex/gpt-5.5
+      ISSUE_ANALYSIS_THINKING: high
+    steps:
+      - name: Create high-entropy working directory name
+        id: workdir
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const crypto = require('crypto');
+            core.setOutput('name', `pi-ci-${crypto.randomBytes(16).toString('hex')}`);
+
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          path: ${{ steps.workdir.outputs.name }}
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+          cache-dependency-path: ${{ steps.workdir.outputs.name }}/package-lock.json
+
+      - name: Install system dependencies (Linux)
+        if: needs.authorize.outputs.runner_os == 'linux'
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y fd-find ripgrep
+          sudo ln -sf "$(which fdfind)" /usr/local/bin/fd
+
+      - name: Install system dependencies (macOS)
+        if: needs.authorize.outputs.runner_os == 'macos'
+        run: |
+          if ! command -v fd >/dev/null 2>&1; then
+            brew install fd
+          fi
+          if ! command -v rg >/dev/null 2>&1; then
+            brew install ripgrep
+          fi
+
+      - name: Install system dependencies (Windows)
+        if: needs.authorize.outputs.runner_os == 'windows'
+        shell: pwsh
+        run: |
+          $packages = @()
+          if (-not (Get-Command fd -ErrorAction SilentlyContinue)) {
+            $packages += "fd"
+          }
+          if (-not (Get-Command rg -ErrorAction SilentlyContinue)) {
+            $packages += "ripgrep"
+          }
+          if ($packages.Count -gt 0) {
+            if (-not (Get-Command choco -ErrorAction SilentlyContinue)) {
+              throw "fd and ripgrep must be installed on Windows runners, or Chocolatey must be available to install them."
+            }
+            choco install $packages -y --no-progress
+          }
+          fd --version
+          rg --version
+
+      - name: Install dependencies
+        working-directory: ${{ steps.workdir.outputs.name }}
+        run: npm ci --ignore-scripts
+
+      - name: Build
+        working-directory: ${{ steps.workdir.outputs.name }}
+        run: npm run build
+
+      - name: Write auth.json
+        id: write_auth
+        uses: actions/github-script@v7
+        env:
+          PI_AUTH_JSON: ${{ secrets.PI_AUTH_JSON }}
+        with:
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+
+            const authJson = process.env.PI_AUTH_JSON;
+            if (!authJson) {
+              throw new Error('PI_AUTH_JSON secret is not configured for the pi-analyze environment');
+            }
+
+            const agentDir = path.join(process.env.RUNNER_TEMP, 'pi-agent');
+            fs.mkdirSync(agentDir, { recursive: true });
+            const authPath = path.join(agentDir, 'auth.json');
+            fs.writeFileSync(authPath, authJson, { mode: 0o600 });
+            if (process.platform !== 'win32') {
+              fs.chmodSync(authPath, 0o600);
+            }
+
+      - name: Run pi /is
+        uses: actions/github-script@v7
+        env:
+          PI_CODING_AGENT_DIR: ${{ runner.temp }}/pi-agent
+          GH_TOKEN: ${{ github.token }}
+          ISSUE_URL: ${{ github.event.issue.html_url }}
+          EXTRA_INSTRUCTIONS: ${{ needs.authorize.outputs.extra_instructions }}
+          WORKDIR: ${{ steps.workdir.outputs.name }}
+        with:
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+            const { spawn } = require('child_process');
+
+            const workdir = path.join(process.env.GITHUB_WORKSPACE, process.env.WORKDIR);
+            const outDir = path.join(process.env.RUNNER_TEMP, 'pi-out');
+            const sessionDir = path.join(outDir, 'session');
+            fs.mkdirSync(sessionDir, { recursive: true });
+
+            let prompt = `/is ${process.env.ISSUE_URL}`;
+            if (process.env.EXTRA_INSTRUCTIONS) {
+              prompt += '\n\nAdditional instructions from @issuron analyze comment:\n';
+              prompt += process.env.EXTRA_INSTRUCTIONS;
+            }
+
+            const outputPath = path.join(outDir, 'output.md');
+            const output = fs.createWriteStream(outputPath);
+            const args = [
+              'packages/coding-agent/src/cli.ts',
+              '-p',
+              '--approve',
+              '--session-dir',
+              sessionDir,
+              '--model',
+              process.env.ISSUE_ANALYSIS_MODEL,
+              '--thinking',
+              process.env.ISSUE_ANALYSIS_THINKING,
+              prompt,
+            ];
+
+            const exitCode = await new Promise((resolve, reject) => {
+              const child = spawn('node', args, {
+                cwd: workdir,
+                env: process.env,
+                stdio: ['ignore', 'pipe', 'pipe'],
+              });
+              child.stdout.on('data', (chunk) => {
+                process.stdout.write(chunk);
+                output.write(chunk);
+              });
+              child.stderr.on('data', (chunk) => {
+                process.stderr.write(chunk);
+              });
+              child.on('error', reject);
+              child.on('close', resolve);
+            });
+            await new Promise((resolve) => output.end(resolve));
+
+            if (exitCode !== 0) {
+              throw new Error(`pi /is failed with exit code ${exitCode}`);
+            }
+
+      - name: Persist refreshed auth.json
+        if: always() && steps.write_auth.outcome == 'success'
+        uses: actions/github-script@v7
+        env:
+          GH_TOKEN: ${{ secrets.PI_AUTH_UPDATE_TOKEN }}
+          PI_CODING_AGENT_DIR: ${{ runner.temp }}/pi-agent
+        with:
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+            const { spawn } = require('child_process');
+
+            if (!process.env.GH_TOKEN) {
+              throw new Error('PI_AUTH_UPDATE_TOKEN is not configured for the pi-analyze environment');
+            }
+
+            const authPath = path.join(process.env.PI_CODING_AGENT_DIR, 'auth.json');
+            if (!fs.existsSync(authPath)) {
+              core.warning('auth.json was not created; skipping auth persistence');
+              return;
+            }
+
+            const authJson = fs.readFileSync(authPath, 'utf8');
+            let parsed;
+            try {
+              parsed = JSON.parse(authJson);
+            } catch (error) {
+              throw new Error(`Refusing to persist malformed auth.json: ${error instanceof Error ? error.message : String(error)}`);
+            }
+
+            const codexAuth = parsed['openai-codex'];
+            if (codexAuth?.type !== 'oauth' || typeof codexAuth.refresh !== 'string' || codexAuth.refresh.length === 0) {
+              throw new Error('Refusing to persist auth.json without openai-codex OAuth refresh credentials');
+            }
+
+            await new Promise((resolve, reject) => {
+              const child = spawn(
+                'gh',
+                ['secret', 'set', 'PI_AUTH_JSON', '--env', 'pi-analyze', '--repo', process.env.GITHUB_REPOSITORY],
+                { env: process.env, stdio: ['pipe', 'inherit', 'inherit'] },
+              );
+              child.stdin.end(authJson);
+              child.on('error', reject);
+              child.on('close', (code) => {
+                if (code === 0) {
+                  resolve();
+                } else {
+                  reject(new Error(`gh secret set failed with exit code ${code}`));
+                }
+              });
+            });
+
+      - name: Export session files
+        id: export_session_files
+        if: always()
+        uses: actions/github-script@v7
+        env:
+          PI_CODING_AGENT_DIR: ${{ runner.temp }}/pi-agent
+          WORKDIR: ${{ steps.workdir.outputs.name }}
+        with:
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+            const { spawn } = require('child_process');
+
+            function findFirstJsonl(dir) {
+              if (!fs.existsSync(dir)) return undefined;
+              const entries = fs.readdirSync(dir, { withFileTypes: true });
+              for (const entry of entries) {
+                const entryPath = path.join(dir, entry.name);
+                if (entry.isDirectory()) {
+                  const nested = findFirstJsonl(entryPath);
+                  if (nested) return nested;
+                } else if (entry.isFile() && entry.name.endsWith('.jsonl')) {
+                  return entryPath;
+                }
+              }
+              return undefined;
+            }
+
+            const outDir = path.join(process.env.RUNNER_TEMP, 'pi-out');
+            const sessionFile = findFirstJsonl(path.join(outDir, 'session'));
+            if (!sessionFile) {
+              throw new Error('No session jsonl file found');
+            }
+
+            const sessionJsonl = path.join(outDir, 'session.jsonl');
+            const sessionHtml = path.join(outDir, 'session.html');
+            fs.copyFileSync(sessionFile, sessionJsonl);
+
+            const workdir = path.join(process.env.GITHUB_WORKSPACE, process.env.WORKDIR);
+            const exitCode = await new Promise((resolve, reject) => {
+              const child = spawn(
+                'node',
+                ['packages/coding-agent/src/cli.ts', '--no-extensions', '--export', sessionJsonl, sessionHtml],
+                { cwd: workdir, env: process.env, stdio: 'inherit' },
+              );
+              child.on('error', reject);
+              child.on('close', resolve);
+            });
+            if (exitCode !== 0) {
+              throw new Error(`session export failed with exit code ${exitCode}`);
+            }
+
+      - name: Upload session gist
+        id: gist
+        if: always() && steps.export_session_files.outcome == 'success'
+        uses: actions/github-script@v7
+        env:
+          PI_GIST_TOKEN: ${{ secrets.PI_GIST_TOKEN }}
+        with:
+          github-token: ${{ secrets.PI_GIST_TOKEN }}
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+
+            if (!process.env.PI_GIST_TOKEN) {
+              throw new Error('PI_GIST_TOKEN is not configured');
+            }
+
+            const outDir = path.join(process.env.RUNNER_TEMP, 'pi-out');
+            const files = {};
+            for (const filename of ['session.html', 'session.jsonl']) {
+              files[filename] = { content: fs.readFileSync(path.join(outDir, filename), 'utf8') };
+            }
+
+            const response = await github.rest.gists.create({
+              public: false,
+              files,
+            });
+            const gistUrl = response.data.html_url;
+            const gistId = response.data.id;
+            core.setOutput('url', gistUrl);
+            core.setOutput('id', gistId);
+            core.setOutput('share_url', `https://pi.dev/session/#${gistId}`);
+
+      - name: Comment with session import instructions
+        if: always() && steps.gist.outcome == 'success'
+        uses: actions/github-script@v7
+        env:
+          GIST_URL: ${{ steps.gist.outputs.url }}
+          GIST_ID: ${{ steps.gist.outputs.id }}
+          SHARE_URL: ${{ steps.gist.outputs.share_url }}
+          SESSION_JSONL: ${{ runner.temp }}/pi-out/session.jsonl
+        with:
+          script: |
+            const fs = require('fs');
+
+            function extractLastAgentMessage(sessionPath) {
+              const lines = fs.readFileSync(sessionPath, 'utf8').split(/\r?\n/).filter(Boolean);
+              let lastText = '';
+
+              for (const line of lines) {
+                let entry;
+                try {
+                  entry = JSON.parse(line);
+                } catch {
+                  continue;
+                }
+
+                if (entry.type !== 'message' || entry.message?.role !== 'assistant') continue;
+
+                const content = entry.message.content;
+                const parts = [];
+                if (typeof content === 'string') {
+                  parts.push(content);
+                } else if (Array.isArray(content)) {
+                  for (const block of content) {
+                    if (block?.type === 'text' && typeof block.text === 'string') {
+                      parts.push(block.text);
+                    }
+                  }
+                }
+
+                const text = parts.join('\n\n').trim();
+                if (text) lastText = text;
+              }
+
+              if (!lastText) return '_No assistant output found._';
+              const maxLength = 55000;
+              if (lastText.length <= maxLength) return lastText;
+              return `${lastText.slice(0, maxLength)}\n\n_[truncated]_`;
+            }
+
+            const gistUrl = process.env.GIST_URL;
+            const gistId = process.env.GIST_ID;
+            const shareUrl = process.env.SHARE_URL;
+            const lastAgentMessage = extractLastAgentMessage(process.env.SESSION_JSONL);
+            const body = [
+              'Pi issue analysis finished.',
+              '',
+              `Share URL: ${shareUrl}`,
+              `Gist: ${gistUrl}`,
+              '',
+              'Continue locally from a checkout with:',
+              '',
+              '```sh',
+              `pi "/ir ${gistId}"`,
+              '```',
+              '',
+              '<details>',
+              '<summary>Agent analysis summary</summary>',
+              '',
+              lastAgentMessage,
+              '',
+              '</details>',
+            ].join('\n');
+
+            await github.rest.issues.createComment({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+              body,
+            });
+
+      - name: Remove trigger label
+        if: always()
+        uses: actions/github-script@v7
+        with:
+          script: |
+            try {
+              await github.rest.issues.removeLabel({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                name: 'pi-analyze',
+              });
+            } catch (error) {
+              if (error.status !== 404) throw error;
+            }

.github/workflows/issue-gate.yml

@@ -17,11 +17,13 @@ jobs:
           script: |
             const APPROVED_FILE = '.github/APPROVED_CONTRIBUTORS';
             const VALID_CAPABILITIES = new Set(['issue', 'pr']);
+            const TRUSTED_BOT_AUTHORS = new Set(['dependabot[bot]', 'sentry[bot]', 'claude[bot]']);
             const issueAuthor = context.payload.issue.user.login;
             const defaultBranch = context.payload.repository.default_branch;
+            const isBotAuthor = issueAuthor.endsWith('[bot]');
 
-            if (issueAuthor.endsWith('[bot]') || issueAuthor === 'dependabot[bot]') {
-              console.log(`Skipping bot: ${issueAuthor}`);
+            if (TRUSTED_BOT_AUTHORS.has(issueAuthor)) {
+              console.log(`Skipping trusted bot: ${issueAuthor}`);
               return;
             }
 
@@ -80,7 +82,7 @@ jobs:
             }
 
             const permission = await getPermission(issueAuthor);
-            if (['admin', 'maintain', 'write'].includes(permission)) {
+            if (!isBotAuthor && ['admin', 'maintain', 'write'].includes(permission)) {
               console.log(`${issueAuthor} is a collaborator with ${permission} access`);
               return;
             }
@@ -89,7 +91,7 @@ jobs:
             const approvedUsers = parseApprovedUsers(approvedContent);
             const capability = approvedUsers.get(issueAuthor.toLowerCase());
 
-            if (capability === 'issue' || capability === 'pr') {
+            if (!isBotAuthor && (capability === 'issue' || capability === 'pr')) {
               console.log(`${issueAuthor} is approved for ${capability}`);
               return;
             }

.github/workflows/openclaw-gate.yml

@@ -1,122 +0,0 @@
-name: OpenClaw Gate
-
-on:
-  issues:
-    types: [opened]
-  pull_request_target:
-    types: [opened]
-
-jobs:
-  check-contributor:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      issues: write
-      pull-requests: write
-    steps:
-      - name: Check contributor
-        uses: actions/github-script@v7
-        with:
-          script: |
-            const isPR = !!context.payload.pull_request;
-            const author = isPR
-              ? context.payload.pull_request.user.login
-              : context.payload.issue.user.login;
-            const number = isPR
-              ? context.payload.pull_request.number
-              : context.payload.issue.number;
-            const defaultBranch = context.payload.repository.default_branch;
-
-            if (author.endsWith('[bot]') || author === 'dependabot[bot]') {
-              console.log(`Skipping bot: ${author}`);
-              return;
-            }
-
-            const APPROVED_FILE = '.github/APPROVED_CONTRIBUTORS';
-            const VALID_CAPABILITIES = new Set(['issue', 'pr']);
-
-            // --- Check APPROVED_CONTRIBUTORS ---
-            async function getTextFile(path) {
-              const { data } = await github.rest.repos.getContent({
-                owner: context.repo.owner,
-                repo: context.repo.repo,
-                path,
-                ref: defaultBranch,
-              });
-              if (!('content' in data) || typeof data.content !== 'string') {
-                throw new Error(`Expected file content for ${path}`);
-              }
-              return Buffer.from(data.content, 'base64').toString('utf8');
-            }
-
-            try {
-              const content = await getTextFile(APPROVED_FILE);
-              const approved = new Map();
-              for (const rawLine of content.split('\n')) {
-                const line = rawLine.trim();
-                if (!line || line.startsWith('#')) continue;
-
-                const parts = line.split(/\s+/);
-                if (parts.length !== 2) continue;
-
-                const [username, capability] = parts;
-                const normalizedCapability = capability.toLowerCase();
-                if (!VALID_CAPABILITIES.has(normalizedCapability)) continue;
-
-                approved.set(username.toLowerCase(), normalizedCapability);
-              }
-
-              if (approved.has(author.toLowerCase())) {
-                console.log(`${author} is in APPROVED_CONTRIBUTORS, passing`);
-                return;
-              }
-            } catch (err) {
-              console.log(`Could not read APPROVED_CONTRIBUTORS: ${err.message}`);
-            }
-
-            // --- Also pass collaborators with write+ access ---
-            try {
-              const { data: perm } = await github.rest.repos.getCollaboratorPermissionLevel({
-                owner: context.repo.owner,
-                repo: context.repo.repo,
-                username: author,
-              });
-              if (['admin', 'maintain', 'write'].includes(perm.permission)) {
-                console.log(`${author} is a collaborator (${perm.permission}), passing`);
-                return;
-              }
-            } catch {
-              // not a collaborator
-            }
-
-            // --- Check if user opened issues/PRs on openclaw/openclaw ---
-            async function hasOpenClawActivity(username) {
-              try {
-                const { data } = await github.rest.search.issuesAndPullRequests({
-                  q: `repo:openclaw/openclaw author:${username}`,
-                  per_page: 1,
-                });
-                if (data.total_count > 0) {
-                  console.log(`${username} has opened ${data.total_count} issues/PRs on openclaw/openclaw`);
-                  return true;
-                }
-              } catch (err) {
-                console.log(`Search failed: ${err.message}`);
-              }
-              return false;
-            }
-
-            const hasActivity = await hasOpenClawActivity(author);
-            if (!hasActivity) {
-              console.log(`${author} has no openclaw/openclaw activity, passing`);
-              return;
-            }
-
-            // --- Add openclaw label ---
-            console.log(`${author} has openclaw/openclaw activity, adding label`);
-            await github.rest.issues.addLabels({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              issue_number: number,
-              labels: ['possibly-openclaw-clanker'],
-            });

.github/workflows/pr-gate.yml

@@ -18,11 +18,13 @@ jobs:
           script: |
             const APPROVED_FILE = '.github/APPROVED_CONTRIBUTORS';
             const VALID_CAPABILITIES = new Set(['issue', 'pr']);
+            const TRUSTED_BOT_AUTHORS = new Set(['dependabot[bot]', 'sentry[bot]', 'claude[bot]']);
             const prAuthor = context.payload.pull_request.user.login;
             const defaultBranch = context.payload.repository.default_branch;
+            const isBotAuthor = prAuthor.endsWith('[bot]');
 
-            if (prAuthor.endsWith('[bot]') || prAuthor === 'dependabot[bot]') {
-              console.log(`Skipping bot: ${prAuthor}`);
+            if (TRUSTED_BOT_AUTHORS.has(prAuthor)) {
+              console.log(`Skipping trusted bot: ${prAuthor}`);
               return;
             }
 
@@ -97,7 +99,7 @@ jobs:
             }
 
             const permission = await getPermission(prAuthor);
-            if (['admin', 'maintain', 'write'].includes(permission)) {
+            if (!isBotAuthor && ['admin', 'maintain', 'write'].includes(permission)) {
               console.log(`${prAuthor} is a collaborator with ${permission} access`);
               return;
             }
@@ -106,7 +108,7 @@ jobs:
             const approvedUsers = parseApprovedUsers(approvedContent);
             const capability = approvedUsers.get(prAuthor.toLowerCase());
 
-            if (capability === 'pr') {
+            if (!isBotAuthor && capability === 'pr') {
               console.log(`${prAuthor} is approved for PRs`);
               return;
             }

.pi/extensions/import-repro.ts

@@ -0,0 +1,351 @@
+/**
+ * Import a pi session shared as a gist by the issue-analysis CI workflow
+ * (.github/workflows/issue-analysis.yml) and switch to it.
+ *
+ * The CI job runs in a high-entropy checkout directory; this command rewrites
+ * the recorded cwd to the local checkout, installs the session file into the
+ * current session directory, and switches to it.
+ *
+ * Usage:
+ *   /ir b4d100022aefb12f25dd2d8485e0a82a
+ *   /ir https://gist.github.com/mitsuhiko/b4d100022aefb12f25dd2d8485e0a82a
+ *   /ir https://pi.dev/session/#b4d100022aefb12f25dd2d8485e0a82a
+ *   /ir https://github.com/earendil-works/pi/issues/123
+ *
+ *   pi "/ir <gist-id>"
+ */
+
+import { Buffer } from "node:buffer";
+import { existsSync, readFileSync, writeFileSync } from "node:fs";
+import { basename, isAbsolute, join, resolve } from "node:path";
+import type { ExtensionAPI, ExtensionCommandContext } from "@earendil-works/pi-coding-agent";
+
+const GIST_ID_RE = /^[0-9a-fA-F]{20,}$/;
+const GIST_URL_RE = /^https:\/\/gist\.github\.com\/(?:[^/]+\/)?([0-9a-fA-F]{20,})(?:[/#?].*)?$/;
+const SHARE_URL_RE = /^https:\/\/pi\.dev\/session\/#([0-9a-fA-F]{20,})(?:[/#?].*)?$/;
+const ISSUE_URL_RE = /^https:\/\/github\.com\/([^/]+)\/([^/]+)\/issues\/(\d+)(?:[/#?].*)?$/;
+const GIST_URL_IN_TEXT_RE = /https:\/\/gist\.github\.com\/(?:[^/\s]+\/)?([0-9a-fA-F]{20,})\b/g;
+const SESSION_DATA_RE = /<script id="session-data" type="application\/json">([^<]+)<\/script>/;
+
+interface SessionHeader {
+	type: "session";
+	id: string;
+	cwd: string;
+	[key: string]: unknown;
+}
+
+interface ExportedSessionData {
+	header: SessionHeader | null;
+	entries: Array<Record<string, unknown>>;
+}
+
+interface GistFile {
+	filename?: string;
+	raw_url?: string;
+	content?: string;
+	truncated?: boolean;
+}
+
+interface GistResponse {
+	files?: Record<string, GistFile>;
+}
+
+interface IssueComment {
+	body?: string | null;
+	user?: { login?: string } | null;
+}
+
+function parseRef(
+	ref: string,
+	cwd: string,
+): { type: "gist"; id: string } | { type: "file"; path: string } | { type: "issue"; owner: string; repo: string; issue: string } {
+	if (ref.endsWith(".html") || ref.endsWith(".jsonl")) {
+		return { type: "file", path: isAbsolute(ref) ? ref : resolve(cwd, ref) };
+	}
+
+	const shareMatch = ref.match(SHARE_URL_RE);
+	if (shareMatch) return { type: "gist", id: shareMatch[1] };
+
+	const gistMatch = ref.match(GIST_URL_RE);
+	if (gistMatch) return { type: "gist", id: gistMatch[1] };
+
+	const issueMatch = ref.match(ISSUE_URL_RE);
+	if (issueMatch) return { type: "issue", owner: issueMatch[1], repo: issueMatch[2], issue: issueMatch[3] };
+
+	if (GIST_ID_RE.test(ref)) return { type: "gist", id: ref };
+
+	throw new Error(`expected a gist ID, gist URL, pi.dev share URL, issue URL, .html file, or .jsonl file: ${ref}`);
+}
+
+function parseSessionJsonl(raw: string): { header: SessionHeader; jsonl: string } {
+	const newlineIndex = raw.indexOf("\n");
+	const firstLine = newlineIndex === -1 ? raw : raw.slice(0, newlineIndex);
+	let parsed: unknown;
+	try {
+		parsed = JSON.parse(firstLine);
+	} catch {
+		throw new Error("first line of session file is not valid JSON");
+	}
+	const header = parsed as Partial<SessionHeader>;
+	if (header.type !== "session" || typeof header.id !== "string" || typeof header.cwd !== "string" || header.cwd === "") {
+		throw new Error("session file has no valid session header with a cwd");
+	}
+	return { header: header as SessionHeader, jsonl: raw };
+}
+
+function decodeExportedHtml(html: string): { header: SessionHeader; jsonl: string } {
+	const match = html.match(SESSION_DATA_RE);
+	if (!match) throw new Error("HTML does not contain embedded pi session data");
+
+	let data: unknown;
+	try {
+		data = JSON.parse(Buffer.from(match[1], "base64").toString("utf8"));
+	} catch {
+		throw new Error("embedded pi session data is not valid JSON");
+	}
+
+	const sessionData = data as Partial<ExportedSessionData>;
+	const header = sessionData.header;
+	if (!header || header.type !== "session" || typeof header.id !== "string" || typeof header.cwd !== "string") {
+		throw new Error("embedded pi session data has no valid session header");
+	}
+	if (!Array.isArray(sessionData.entries)) {
+		throw new Error("embedded pi session data has no entries array");
+	}
+
+	const lines = [header, ...sessionData.entries].map((entry) => JSON.stringify(entry));
+	return { header, jsonl: `${lines.join("\n")}\n` };
+}
+
+type SessionPlatform = "windows" | "unix" | "unknown";
+
+function escapeJsonString(value: string): string {
+	return JSON.stringify(value).slice(1, -1);
+}
+
+function escapeRegExp(value: string): string {
+	return value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+}
+
+function trimTrailingPathSeparators(value: string): string {
+	return value.replace(/[\\/]+$/, "");
+}
+
+function getPathTailName(value: string): string {
+	const trimmed = trimTrailingPathSeparators(value);
+	return trimmed.split(/[\\/]/).filter(Boolean).at(-1) ?? "";
+}
+
+function getWindowsDrivePathParts(value: string): { drive: string; rest: string } | undefined {
+	const trimmed = trimTrailingPathSeparators(value);
+	const driveMatch = trimmed.match(/^([A-Za-z]):[\\/](.*)$/);
+	if (driveMatch) {
+		return { drive: driveMatch[1].toUpperCase(), rest: driveMatch[2].replace(/[\\/]+/g, "/") };
+	}
+
+	const msysMatch = trimmed.match(/^\/([A-Za-z])\/(.*)$/);
+	if (msysMatch) {
+		return { drive: msysMatch[1].toUpperCase(), rest: msysMatch[2].replace(/[\\/]+/g, "/") };
+	}
+
+	return undefined;
+}
+
+function getCwdRewriteVariants(sourceCwd: string): string[] {
+	const trimmed = trimTrailingPathSeparators(sourceCwd);
+	const variants = new Set<string>();
+	if (trimmed) variants.add(trimmed);
+
+	const driveParts = getWindowsDrivePathParts(trimmed);
+	if (driveParts) {
+		const rest = driveParts.rest.replace(/^\/+|\/+$/g, "");
+		const backslashRest = rest.replace(/\//g, "\\");
+		variants.add(`${driveParts.drive}:\\${backslashRest}`);
+		variants.add(`${driveParts.drive}:/${rest}`);
+		variants.add(`/${driveParts.drive.toLowerCase()}/${rest}`);
+		variants.add(`/${driveParts.drive}/${rest}`);
+	}
+
+	return Array.from(variants).filter(Boolean).sort((a, b) => b.length - a.length);
+}
+
+function getCiWorkdirName(sourceCwd: string): string | undefined {
+	const name = getPathTailName(sourceCwd);
+	return /^pi-ci-[0-9a-f]{32}$/i.test(name) ? name : undefined;
+}
+
+function detectSessionPlatform(cwd: string): SessionPlatform {
+	if (/^[A-Za-z]:[\\/]/.test(cwd) || /^\/[A-Za-z]\//.test(cwd)) return "windows";
+	if (cwd.startsWith("/")) return "unix";
+	return "unknown";
+}
+
+function getLocalPlatform(): Exclude<SessionPlatform, "unknown"> {
+	return process.platform === "win32" ? "windows" : "unix";
+}
+
+function getPlatformContinuationNotice(sourceCwd: string): string | undefined {
+	const sourcePlatform = detectSessionPlatform(sourceCwd);
+	const localPlatform = getLocalPlatform();
+	if (sourcePlatform === "unknown" || sourcePlatform === localPlatform) return undefined;
+	if (localPlatform === "unix") {
+		return "This session was continued on a non-Windows machine; paths are now Unix style.";
+	}
+	return "This session was continued on a Windows machine; paths are now Windows style.";
+}
+
+/** Rewrite occurrences of the recorded CI cwd (JSON-escaped) to the target cwd. */
+function rewriteSessionCwd(raw: string, sourceCwd: string, targetCwd: string): string {
+	const target = escapeJsonString(targetCwd);
+	let rewritten = raw;
+
+	for (const sourceVariant of getCwdRewriteVariants(sourceCwd)) {
+		if (sourceVariant === targetCwd) continue;
+		rewritten = rewritten.split(escapeJsonString(sourceVariant)).join(target);
+	}
+
+	const ciWorkdirName = getCiWorkdirName(sourceCwd);
+	if (ciWorkdirName) {
+		const escapedName = escapeRegExp(ciWorkdirName);
+		const windowsPathPatterns = [
+			new RegExp(`[A-Za-z]:(?:[^"\\r\\n])*?${escapedName}`, "g"),
+			new RegExp(`/[A-Za-z]/(?:[^"\\r\\n])*?${escapedName}`, "g"),
+		];
+		for (const pattern of windowsPathPatterns) {
+			rewritten = rewritten.replace(pattern, target);
+		}
+	}
+
+	return rewritten;
+}
+
+async function fetchText(url: string): Promise<string> {
+	const response = await fetch(url, { headers: { Accept: "application/vnd.github+json" } });
+	if (!response.ok) {
+		throw new Error(`failed to fetch ${url}: HTTP ${response.status}`);
+	}
+	return await response.text();
+}
+
+async function readGistFile(file: GistFile): Promise<string> {
+	if (file.content && !file.truncated) return file.content;
+	if (!file.raw_url) throw new Error(`gist file ${file.filename ?? "<unknown>"} has no raw URL`);
+	return await fetchText(file.raw_url);
+}
+
+async function findIssueGistId(owner: string, repo: string, issue: string): Promise<string> {
+	const gistIds: string[] = [];
+	let page = 1;
+	while (true) {
+		const response = await fetch(
+			`https://api.github.com/repos/${encodeURIComponent(owner)}/${encodeURIComponent(repo)}/issues/${encodeURIComponent(issue)}/comments?per_page=100&page=${page}`,
+			{ headers: { Accept: "application/vnd.github+json", "X-GitHub-Api-Version": "2022-11-28" } },
+		);
+		if (!response.ok) throw new Error(`failed to fetch issue comments: HTTP ${response.status}`);
+
+		const comments = (await response.json()) as IssueComment[];
+		for (const comment of comments) {
+			if (comment.user?.login !== "github-actions[bot]") continue;
+			for (const match of (comment.body ?? "").matchAll(GIST_URL_IN_TEXT_RE)) {
+				gistIds.push(match[1]);
+			}
+		}
+
+		if (comments.length < 100) break;
+		page++;
+	}
+
+	const gistId = gistIds.at(-1);
+	if (!gistId) throw new Error(`no github-actions gist link found in comments on ${owner}/${repo}#${issue}`);
+	return gistId;
+}
+
+async function fetchGistSession(gistId: string): Promise<{ header: SessionHeader; jsonl: string }> {
+	const response = await fetch(`https://api.github.com/gists/${gistId}`, {
+		headers: {
+			Accept: "application/vnd.github+json",
+			"X-GitHub-Api-Version": "2022-11-28",
+		},
+	});
+	if (!response.ok) throw new Error(`failed to fetch gist ${gistId}: HTTP ${response.status}`);
+
+	const gist = (await response.json()) as GistResponse;
+	const files = Object.values(gist.files ?? {});
+	const jsonlFile = files.find((file) => file.filename?.endsWith(".jsonl"));
+	if (jsonlFile) return parseSessionJsonl(await readGistFile(jsonlFile));
+
+	const htmlFile = files.find((file) => file.filename?.endsWith(".html"));
+	if (htmlFile) return decodeExportedHtml(await readGistFile(htmlFile));
+
+	throw new Error(`gist ${gistId} has no .jsonl or .html session file`);
+}
+
+export default function (pi: ExtensionAPI) {
+	pi.registerCommand("ir", {
+		description: "Import a CI issue-analysis session from a gist ID, share URL, or issue URL and switch to it",
+		handler: async (args: string, ctx: ExtensionCommandContext) => {
+			const ref = args.trim();
+			if (!ref) {
+				ctx.ui.notify("Usage: /ir <gist-id | gist-url | pi.dev/session URL | issue URL>", "error");
+				return;
+			}
+
+			try {
+				const targetCwd = ctx.sessionManager.getCwd();
+				const sessionDir = ctx.sessionManager.getSessionDir();
+				const parsedRef = parseRef(ref, targetCwd);
+
+				ctx.ui.notify(`Importing repro session from ${ref}...`, "info");
+
+				let sourceName: string;
+				let decoded: { header: SessionHeader; jsonl: string };
+				if (parsedRef.type === "gist") {
+					decoded = await fetchGistSession(parsedRef.id);
+					sourceName = `${parsedRef.id}.jsonl`;
+				} else if (parsedRef.type === "issue") {
+					const gistId = await findIssueGistId(parsedRef.owner, parsedRef.repo, parsedRef.issue);
+					decoded = await fetchGistSession(gistId);
+					sourceName = `${gistId}.jsonl`;
+				} else {
+					if (!existsSync(parsedRef.path)) throw new Error(`session file not found: ${parsedRef.path}`);
+					const raw = readFileSync(parsedRef.path, "utf8");
+					decoded = parsedRef.path.endsWith(".html") ? decodeExportedHtml(raw) : parseSessionJsonl(raw);
+					sourceName = basename(parsedRef.path).replace(/\.html$/, ".jsonl");
+				}
+
+				const platformNotice = getPlatformContinuationNotice(decoded.header.cwd);
+				const rewritten = rewriteSessionCwd(decoded.jsonl, decoded.header.cwd, targetCwd);
+				const destination = join(sessionDir, sourceName);
+				if (existsSync(destination)) {
+					const overwrite = await ctx.ui.confirm(
+						"Session already imported",
+						`Overwrite ${destination}? Local changes to that session will be lost.`,
+					);
+					if (!overwrite) {
+						ctx.ui.notify("Import cancelled", "warning");
+						return;
+					}
+				}
+				writeFileSync(destination, rewritten);
+
+				ctx.ui.notify(`Imported session ${decoded.header.id} (cwd ${decoded.header.cwd} -> ${targetCwd})`, "info");
+				await ctx.switchSession(destination, {
+					withSession: async (nextCtx) => {
+						if (!platformNotice) return;
+						await nextCtx.sendMessage(
+							{
+								customType: "import-repro",
+								content: platformNotice,
+								display: true,
+								details: { sourceCwd: decoded.header.cwd, targetCwd },
+							},
+							{ triggerTurn: false },
+						);
+					},
+				});
+			} catch (error) {
+				ctx.ui.notify(`ir: ${error instanceof Error ? error.message : String(error)}`, "error");
+			}
+		},
+	});
+}

.pi/prompts/is.md

@@ -6,7 +6,7 @@ Analyze GitHub issue(s): $ARGUMENTS
 
 For each issue:
 
-1. Add the `inprogress` label to the issue via GitHub CLI and assign the issue to the local `gh` user before analysis starts. If either action fails, report that explicitly and continue.
+1. If running under CI (`CI=true`), do not add the `inprogress` label and do not assign the issue. Otherwise, add the `inprogress` label to the issue via GitHub CLI and assign the issue to the local `gh` user before analysis starts. If either action fails, report that explicitly and continue.
 2. Read the issue in full, including all comments and linked issues/PRs. Use fields supported by GitHub CLI, for example:
    ```sh
    gh issue view <issue> --json title,body,comments,labels,assignees,state,url,author,createdAt,updatedAt,closedByPullRequestsReferences

.pi/prompts/wr.md

@@ -25,6 +25,11 @@ Unless I explicitly override something in this request, do the following in orde
 4. If this task is tied to exactly one GitHub issue, include `closes #<issue>` in the commit message. If it is tied to multiple issues, stop and ask which one to use. If it is not tied to any issue, do not include `closes #` or `fixes #` in the commit message.
 5. Check the current git branch. If it is not `main`, stop and ask what to do. Do not push from another branch unless I explicitly say so.
 6. Push the current branch.
+7. If this task is tied to exactly one GitHub issue, explicitly close that issue with reason `completed` after the push so the issue-close workflows in `.github/` run. This applies to issues only, not PRs.
+   - Inspect `gh issue view <issue> --json state,stateReason,labels`.
+   - If the issue is open, run `gh issue close <issue> --reason completed`.
+   - If the issue is already closed with any reason other than `COMPLETED`, reopen it first, then close it with `gh issue close <issue> --reason completed` so GitHub emits a fresh close event.
+   - If the issue is already closed as `COMPLETED`, leave it closed unless the `inprogress` label is still present; in that case reopen it and close it again with reason `completed`.
 
 Constraints:
 - Never stage unrelated files.

biome.json

@@ -31,6 +31,7 @@
 			"!**/node_modules/**/*",
 			"!**/test-sessions.ts",
 			"!**/models.generated.ts",
+			"!**/*.models.ts",
 			"!packages/mom/data/**/*",
 			"!!**/node_modules"
 		]

package-lock.json

@@ -773,9 +773,9 @@
 			}
 		},
 		"node_modules/@earendil-works/gondolin/node_modules/undici": {
-			"version": "6.26.0",
-			"resolved": "https://registry.npmjs.org/undici/-/undici-6.26.0.tgz",
-			"integrity": "sha512-4yqz8a3n5HmGTlsbADNtr/dJlhkh/55Rq798G6ibiULcXbDtaLpTl1pvdqcbFfeoj3iSi52lePFM7h9H21cw/A==",
+			"version": "6.27.0",
+			"resolved": "https://registry.npmjs.org/undici/-/undici-6.27.0.tgz",
+			"integrity": "sha512-YmfV3YnEDzXRC5lZ2jWtWWHKGUm1zIt8AhesR1tens+HTNv+YZlN/dp6G727LOvMJ8xjP9Be7Y2Sdr96LDm+pg==",
 			"license": "MIT",
 			"engines": {
 				"node": ">=18.17"
@@ -793,6 +793,10 @@
 			"resolved": "packages/coding-agent",
 			"link": true
 		},
+		"node_modules/@earendil-works/pi-orchestrator": {
+			"resolved": "packages/orchestrator",
+			"link": true
+		},
 		"node_modules/@earendil-works/pi-tui": {
 			"resolved": "packages/tui",
 			"link": true
@@ -5111,10 +5115,10 @@
 		},
 		"packages/agent": {
 			"name": "@earendil-works/pi-agent-core",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"license": "MIT",
 			"dependencies": {
-				"@earendil-works/pi-ai": "^0.79.10",
+				"@earendil-works/pi-ai": "^0.80.3",
 				"ignore": "7.0.5",
 				"typebox": "1.1.38",
 				"yaml": "2.9.0"
@@ -5463,7 +5467,7 @@
 		},
 		"packages/ai": {
 			"name": "@earendil-works/pi-ai",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"license": "MIT",
 			"dependencies": {
 				"@anthropic-ai/sdk": "0.91.1",
@@ -5769,12 +5773,12 @@
 		},
 		"packages/coding-agent": {
 			"name": "@earendil-works/pi-coding-agent",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"license": "MIT",
 			"dependencies": {
-				"@earendil-works/pi-agent-core": "^0.79.10",
-				"@earendil-works/pi-ai": "^0.79.10",
-				"@earendil-works/pi-tui": "^0.79.10",
+				"@earendil-works/pi-agent-core": "^0.80.3",
+				"@earendil-works/pi-ai": "^0.80.3",
+				"@earendil-works/pi-tui": "^0.80.3",
 				"@silvia-odwyer/photon-node": "0.3.4",
 				"chalk": "5.6.2",
 				"cross-spawn": "7.0.6",
@@ -5815,32 +5819,32 @@
 		},
 		"packages/coding-agent/examples/extensions/custom-provider-anthropic": {
 			"name": "pi-extension-custom-provider-anthropic",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"dependencies": {
 				"@anthropic-ai/sdk": "0.52.0"
 			}
 		},
 		"packages/coding-agent/examples/extensions/custom-provider-gitlab-duo": {
 			"name": "pi-extension-custom-provider-gitlab-duo",
-			"version": "0.79.10"
+			"version": "0.80.3"
 		},
 		"packages/coding-agent/examples/extensions/gondolin": {
 			"name": "pi-extension-gondolin",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"dependencies": {
 				"@earendil-works/gondolin": "0.12.0"
 			}
 		},
 		"packages/coding-agent/examples/extensions/sandbox": {
 			"name": "pi-extension-sandbox",
-			"version": "1.9.10",
+			"version": "1.10.3",
 			"dependencies": {
 				"@anthropic-ai/sandbox-runtime": "0.0.26"
 			}
 		},
 		"packages/coding-agent/examples/extensions/with-deps": {
 			"name": "pi-extension-with-deps",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"dependencies": {
 				"ms": "2.1.3"
 			},
@@ -6134,9 +6138,23 @@
 				}
 			}
 		},
+		"packages/orchestrator": {
+			"name": "@earendil-works/pi-orchestrator",
+			"version": "0.80.3",
+			"license": "MIT",
+			"dependencies": {
+				"@earendil-works/pi-coding-agent": "^0.80.3"
+			},
+			"devDependencies": {
+				"shx": "0.4.0"
+			},
+			"engines": {
+				"node": ">=22.19.0"
+			}
+		},
 		"packages/tui": {
 			"name": "@earendil-works/pi-tui",
-			"version": "0.79.10",
+			"version": "0.80.3",
 			"license": "MIT",
 			"dependencies": {
 				"get-east-asian-width": "1.6.0",

package.json

@@ -12,11 +12,12 @@
 	],
 	"scripts": {
 		"clean": "npm run clean --workspaces",
-		"build": "cd packages/tui && npm run build && cd ../ai && npm run build && cd ../agent && npm run build && cd ../coding-agent && npm run build",
-		"check": "biome check --write --error-on-warnings . && npm run check:pinned-deps && npm run check:ts-imports && npm run check:shrinkwrap && tsgo --noEmit && npm run check:browser-smoke",
+		"build": "cd packages/tui && npm run build && cd ../ai && npm run build && cd ../agent && npm run build && cd ../coding-agent && npm run build && cd ../orchestrator && npm run build",
+		"check": "biome check --write --error-on-warnings . && npm run check:pinned-deps && npm run check:ts-imports && npm run check:shrinkwrap && npm run check:install-lock:coding-agent && tsgo --noEmit && npm run check:browser-smoke",
 		"check:browser-smoke": "node scripts/check-browser-smoke.mjs",
 		"check:pinned-deps": "node scripts/check-pinned-deps.mjs",
 		"check:shrinkwrap": "node scripts/generate-coding-agent-shrinkwrap.mjs --check",
+		"check:install-lock:coding-agent": "node scripts/generate-coding-agent-install-lock.mjs --check",
 		"check:ts-imports": "node scripts/check-ts-relative-imports.mjs",
 		"profile:tui": "node scripts/profile-coding-agent-node.mjs --mode tui",
 		"profile:rpc": "node scripts/profile-coding-agent-node.mjs --mode rpc",
@@ -30,6 +31,7 @@
 		"publish:dry": "npm run prepublishOnly && node scripts/publish.mjs --dry-run",
 		"release:local": "node scripts/local-release.mjs",
 		"shrinkwrap:coding-agent": "node scripts/generate-coding-agent-shrinkwrap.mjs",
+		"install-lock:coding-agent": "node scripts/generate-coding-agent-install-lock.mjs",
 		"release:patch": "node scripts/release.mjs patch",
 		"release:minor": "node scripts/release.mjs minor",
 		"release:major": "node scripts/release.mjs major",

packages/agent/CHANGELOG.md

@@ -1,5 +1,50 @@
 # Changelog
 
+## [Unreleased]
+
+### Added
+
+- Added configurable harness session context entry transforms and custom-entry message projectors.
+- Exported `InMemorySessionStorage` and `JsonlSessionStorage` ([#6435](https://github.com/earendil-works/pi/issues/6435)).
+
+### Fixed
+
+- Fixed harness split-turn compaction to serialize summary requests so single-concurrency providers are not asked to run overlapping generations ([#5536](https://github.com/earendil-works/pi/issues/5536)).
+- Fixed harness session storage short entry ids to use the random tail of the generated uuidv7 instead of the timestamp prefix, which was nearly constant between calls ([#6242](https://github.com/earendil-works/pi/issues/6242)).
+
+## [0.80.3] - 2026-06-30
+
+### Added
+
+- Added `prepareNextTurnWithContext` for `Agent` users that need the next-turn loop context.
+
+### Fixed
+
+- Fixed oversized harness shell execution timeouts to fail with a clear validation error instead of being clamped to an immediate timeout ([#6181](https://github.com/earendil-works/pi/issues/6181)).
+- Fixed `Agent.prepareNextTurn` to keep receiving the run abort signal instead of the next-turn context.
+
+## [0.80.2] - 2026-06-23
+
+### Changed
+
+- Renamed the public harness shell execution options type from `ExecutionEnvExecOptions` to `ShellExecOptions`.
+
+## [0.80.1] - 2026-06-23
+
+## [0.80.0] - 2026-06-23
+
+### Breaking Changes
+
+- `AgentHarnessOptions.models` is required and is the only auth path: the harness streams turns, compaction, and branch summarization through the provided `Models` instance (`models.streamSimple()`/`completeSimple()`), resolving auth through the providers. `AgentHarnessOptions.getApiKeyAndHeaders` is removed — apps that resolved keys per request now express that as provider auth (`ApiKeyAuth`/`OAuthAuth`) on the providers in the `Models` collection. Build one with `createModels()` + provider factories (or `builtinModels()` from `@earendil-works/pi-ai/providers/all`); tests use `fauxProvider()`.
+- `compact()`, `generateSummary()`, and `generateBranchSummary()` take a `Models` parameter and no longer accept explicit `apiKey`/`headers`.
+- `StreamFn` is defined structurally (`(model, context, options?) => AssistantMessageEventStream | Promise<...>`); `Models.streamSimple` satisfies it.
+- Removed the `@earendil-works/pi-agent-core/base` selective-provider entrypoint; use the root package with an explicit `Models` instance instead.
+
+### Fixed
+
+- Fixed harness session names to normalize newline characters before storing labels ([#5999](https://github.com/earendil-works/pi/pull/5999) by [@haoqixu](https://github.com/haoqixu)).
+- Fixed harness compaction estimates to ignore malformed all-zero assistant usage after truncated responses ([#5526](https://github.com/earendil-works/pi/pull/5526) by [@dmmulroy](https://github.com/dmmulroy)).
+
 ## [0.79.10] - 2026-06-22
 
 ## [0.79.9] - 2026-06-20

packages/agent/README.md

@@ -31,24 +31,6 @@ agent.subscribe((event) => {
 await agent.prompt("Hello!");
 ```
 
-## Base Entry Point
-
-Use `@earendil-works/pi-agent-core/base` with `@earendil-works/pi-ai/base` when bundling applications that should include only selected provider transports:
-
-```typescript
-import { Agent } from "@earendil-works/pi-agent-core/base";
-import { getModel } from "@earendil-works/pi-ai/base";
-import { register } from "@earendil-works/pi-ai/anthropic";
-
-register();
-
-const agent = new Agent({
-  initialState: { model: getModel("anthropic", "claude-sonnet-4-6") },
-});
-```
-
-The default `@earendil-works/pi-agent-core` entry point remains batteries-included and registers pi-ai's lazy built-in transports for backward compatibility.
-
 ## Core Concepts
 
 ### AgentMessage vs LLM Message

packages/agent/docs/agent-harness.md

@@ -79,6 +79,8 @@ Stream options are shallow-copied when a snapshot is created. `headers` and `met
 
 The session contains persisted entries only. Session reads return persisted state and do not include queued writes.
 
+`Session.buildContextEntries()` returns the compaction-aware entry sequence used for model context construction. `Session.buildContext()` derives runtime state from the full active branch, then projects those context entries to `AgentMessage[]`. Custom entries are omitted from model context by default; applications can pass `entryProjectors` to the `Session` constructor or `buildContext()` to project selected custom entries into messages. Applications can also pass stacked `entryTransforms`, which run after the default compaction transform, to filter or reorder context entries before projection.
+
 Session storage implementations must persist leaf changes as `leaf` entries. `setLeafId()` is not an in-memory-only cursor update; it appends a durable entry whose `targetId` is the active tree leaf or `null` for root. Reopening storage must reconstruct the current leaf from the latest persisted leaf-affecting entry.
 
 ### Pending session writes

packages/agent/docs/models.md

@@ -0,0 +1,966 @@
+# Models architecture
+
+This document describes the target design for the next `pi-ai` model/provider refactor. It describes the desired shape, not the current implementation. It is intended to be complete enough to start implementing from a fresh session.
+
+Goals:
+
+- `Models` is a dumb runtime collection of providers.
+- Concrete providers own metadata, auth, model listing, and stream behavior.
+- API implementations live under `src/api/` and are reusable/lazy.
+- Concrete provider factories live under `src/providers/`.
+- Users can import only the providers they need.
+- Importing a provider must not eagerly import heavy SDKs.
+- Dynamic model lists are first-class: reads are sync (last-known list), fetching happens in an explicit async `refresh`.
+- `models.json` and extensions layer by wrapping providers, not by mutating provider internals ad hoc.
+- Old global APIs survive only in an explicit, temporary `/compat` entrypoint.
+
+Non-goals for the immediate `pi-ai` pass:
+
+- Do not migrate coding-agent `ModelRegistry` yet.
+- Do not keep the stream/API registry inside `Models`.
+- Do not implement web OAuth flows yet.
+- Image generation mirrors the chat-side design (`ImagesModels`/`ImagesProvider` in `images-models.ts`); the old global image API (`images.ts`, `images-api-registry.ts`) lives on compat.
+
+## Package layout
+
+Target source layout:
+
+```txt
+packages/ai/src/
+  index.ts                    # core exports only; no built-in provider imports
+  models.ts                   # Models runtime, Provider
+  images-models.ts            # ImagesModels runtime, ImagesProvider (mirrors models.ts)
+  compat.ts                   # temporary old-API compatibility entrypoint
+  auth/                       # auth method types, helpers, shared resolveProviderAuth(), login callbacks
+  api/                        # API implementations and lazy wrappers
+    openai-completions.ts     # real implementation, imports SDKs, exports stream/streamSimple
+    openai-completions.lazy.ts
+    openai-responses.ts
+    openai-responses.lazy.ts
+    openai-codex-responses.ts
+    openai-codex-responses.lazy.ts
+    azure-openai-responses.ts
+    azure-openai-responses.lazy.ts
+    anthropic-messages.ts
+    anthropic-messages.lazy.ts
+    google-generative-ai.ts
+    google-generative-ai.lazy.ts
+    google-vertex.ts
+    google-vertex.lazy.ts
+    mistral-conversations.ts
+    mistral-conversations.lazy.ts
+    bedrock-converse-stream.ts
+    bedrock-converse-stream.lazy.ts
+    openrouter-images.ts      # image-generation API implementation
+    openrouter-images.lazy.ts
+    lazy.ts                   # lazyStream()/lazyApi() helpers
+    (shared helpers: openai-responses-shared, google-shared, transform-messages, ...)
+  providers/                  # concrete provider factories and per-provider catalogs
+    openai.ts
+    openai.models.ts          # generated OpenAI catalog
+    openai-codex.ts
+    openai-codex.models.ts
+    anthropic.ts
+    anthropic.models.ts
+    google.ts
+    google.models.ts
+    ...one pair per built-in provider...
+    openrouter-images.ts      # image-generation provider factory
+    faux.ts                   # test provider factory
+    all.ts                    # explicit aggregate: builtinModels(), builtinImagesModels(), getBuiltin*()
+  utils/oauth/                # OAuth flow implementations (node), lazy-loaded
+```
+
+`src/index.ts` must stay core-only. It must not import:
+
+- generated model catalogs
+- built-in provider factories
+- provider SDK implementations
+- Node-only OAuth modules
+- `providers/all`
+- `compat`
+
+Provider, API, and compat entrypoints are explicit subpath exports.
+
+## Public usage
+
+Minimal provider usage:
+
+```ts
+import { createModels } from "@earendil-works/pi-ai";
+import { openaiProvider } from "@earendil-works/pi-ai/providers/openai";
+
+const models = createModels();
+models.setProvider(openaiProvider());
+
+const model = models.getModel("openai", "gpt-4o-mini");
+if (!model) throw new Error("model not found");
+
+const response = await models.complete(model, context);
+```
+
+Multiple providers:
+
+```ts
+const models = createModels();
+models.setProvider(openaiProvider());
+models.setProvider(openrouterProvider());
+```
+
+All built-ins, explicitly heavy metadata entrypoint:
+
+```ts
+import { builtinModels } from "@earendil-works/pi-ai/providers/all";
+
+const models = builtinModels();
+```
+
+`providers/all` may import all provider metadata/catalogs. It still must not eagerly import SDK implementations; provider streams use lazy wrappers.
+
+## Core runtime: Models
+
+`Models` is a provider collection plus auth application and stream convenience. No stream registry, no auth resolver strategy object.
+
+```ts
+export function createModels(options?: {
+  /** App-owned credential storage. Default: in-memory store. */
+  credentials?: CredentialStore;
+  /** Environment access for auth resolution (env vars, file existence). Default: process.env/node:fs backed; injectable for tests and non-Node hosts. */
+  authContext?: AuthContext;
+}): MutableModels;
+
+export interface Models {
+  getProviders(): readonly Provider[];
+  getProvider(id: string): Provider | undefined;
+
+  /** Sync read of last-known models. Best-effort: a provider whose getModels() throws yields no models. */
+  getModels(provider?: string): readonly Model<Api>[];
+  /** Dynamic lists are honestly Model<Api>; narrow with the hasApi() guard. */
+  getModel(provider: string, id: string): Model<Api> | undefined;
+
+  /**
+   * Ask dynamic providers to re-fetch their model lists. With a provider id,
+   * rejects on that provider's failure; without, refreshes all concurrently
+   * best-effort. Static providers are no-ops.
+   */
+  refresh(provider?: string): Promise<void>;
+
+  /**
+   * Resolve request auth for a model. Includes source label for status UI.
+   * Resolves undefined when the provider is unknown or unconfigured. Rejects
+   * with ModelsError ("oauth" on refresh failure, "auth" on api-key/store
+   * failure); status/availability UIs catch rejections and render
+   * "needs re-login" instead of treating them as unconfigured.
+   */
+  getAuth(model: Model<Api>): Promise<AuthResult | undefined>;
+
+  stream<TApi extends Api>(
+    model: Model<TApi>,
+    context: Context,
+    options?: ApiStreamOptions<TApi>,
+  ): AssistantMessageEventStream;
+
+  complete<TApi extends Api>(
+    model: Model<TApi>,
+    context: Context,
+    options?: ApiStreamOptions<TApi>,
+  ): Promise<AssistantMessage>;
+
+  streamSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream;
+  completeSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): Promise<AssistantMessage>;
+}
+
+export interface MutableModels extends Models {
+  /** Upsert/replace by provider.id. Provider ids are unique. */
+  setProvider(provider: Provider): void;
+  deleteProvider(id: string): void;
+  clearProviders(): void;
+}
+```
+
+Removed concepts:
+
+```txt
+no Models.setStreamFunctions() / getStreamFunctions()
+no api-registry as a real dispatch mechanism
+no Models.provider(id) builder, no setModel/upsertModel/patchModel lifecycle
+no ModelAuthResolver / setAuthResolver — resolution policy is fixed, store is injected
+```
+
+If an app needs different auth policy, it wraps providers (wrap auth methods or `getModels`) or passes explicit request auth in stream options.
+
+## Provider
+
+A provider is the concrete runtime unit. It owns id/name/base metadata, auth methods, model listing, and stream behavior.
+
+`Provider` is generic over the APIs its models use. Concrete factories declare what they emit (`openaiProvider(): Provider<"openai-responses" | "openai-completions">`), giving typed model lists to direct factory users. A `Models` collection holds providers as `Provider<Api>`.
+
+```ts
+export interface Provider<TApi extends Api = Api> {
+  readonly id: string;
+  readonly name: string;
+
+  readonly baseUrl?: string;
+  readonly headers?: Record<string, string>;
+
+  /**
+   * Required: at least one of apiKey/oauth. Even ambient-credential providers
+   * (env vars, AWS profiles, ADC) and keyless local servers provide apiKey
+   * auth whose resolve() reports whether the provider is configured.
+   * getAuth() returning undefined = not configured.
+   */
+  readonly auth: ProviderAuth;
+
+  /** Current known models, sync. Static providers: the catalog. Dynamic providers: as of the last refresh (empty before the first). */
+  getModels(): readonly Model<TApi>[];
+
+  /** Dynamic providers only: fetch and update the model list. Concurrent calls share one in-flight fetch. */
+  refreshModels?(): Promise<void>;
+
+  stream<T extends TApi>(model: Model<T>, context: Context, options?: ApiStreamOptions<T>): AssistantMessageEventStream;
+
+  streamSimple(model: Model<TApi>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream;
+}
+```
+
+There is no `Provider.api` field. `model.api` carries API identity; the provider dispatches internally (see `createProvider()`).
+
+`Model.api` remains: existing metadata and tests use it, it is useful for diagnostics, and provider construction uses it for API implementation selection. But `Models` never dispatches on it; the provider does.
+
+### Typed stream options
+
+Full stream options are API-specific. `Model<TApi>` pays off by deriving the option type from the API:
+
+```ts
+// types.ts — type-only imports from API impl modules are erased, so this is tree-shake safe
+export interface ApiOptionsMap {
+  "anthropic-messages": AnthropicOptions;
+  "openai-completions": OpenAICompletionsOptions;
+  "openai-responses": OpenAIResponsesOptions;
+  "openai-codex-responses": OpenAICodexResponsesOptions;
+  "azure-openai-responses": AzureOpenAIResponsesOptions;
+  "google-generative-ai": GoogleOptions;
+  "google-vertex": GoogleVertexOptions;
+  "mistral-conversations": MistralOptions;
+  "bedrock-converse-stream": BedrockOptions;
+}
+
+export type ApiStreamOptions<TApi extends Api> = TApi extends keyof ApiOptionsMap
+  ? ApiOptionsMap[TApi]
+  : StreamOptions & Record<string, unknown>;
+```
+
+Custom api strings fall back to the generic shape.
+
+### Typed model narrowing
+
+Runtime model lists are dynamic, so `models.getModel()`/`getModels()` honestly return `Model<Api>`. Typing improves at three points:
+
+1. **`hasApi()` type guard** — runtime-checked narrowing for dynamic lookups (no blind casts):
+
+   ```ts
+   export function hasApi<TApi extends Api>(model: Model<Api>, api: TApi): model is Model<TApi>;
+
+   const model = models.getModel("anthropic", "claude-opus-4-7");
+   if (model && hasApi(model, "anthropic-messages")) {
+     // model: Model<"anthropic-messages">, stream options fully typed
+   }
+   ```
+
+2. **`getBuiltinModel()`** — sync, generated-catalog lookup with typed overloads: `(provider, id) -> Model<exact-api-literal>`. The path for hardcoded known models.
+
+3. **`Provider<TApi>` factories** — typed model lists when using a provider directly, without a `Models` collection.
+
+Deliberately not done: tying `models.getModel(provider, ...)` to typed provider/model ids would require statically knowing which providers are installed in a mutable runtime collection. The harness path (`streamSimple` + `SimpleStreamOptions`) is API-agnostic and unaffected.
+
+For comparison: Vercel AI SDK attaches the implementation to the model object, which dissolves dispatch typing but makes models non-serializable (no sessions/RPC/catalogs as plain data), and its `providerOptions` bag is `Record<string, JSON>` checked only by `satisfies` convention. Plain-data models + provider-owned behavior keeps stronger typing where it matters.
+
+### Name collision
+
+`types.ts` currently exports `type Provider = KnownProvider | string` (a provider id). Rename that alias to `ProviderId` and fix call sites. The `Provider` interface above takes the name.
+
+## Provider model listing
+
+Reads are sync; fetching is an explicit async verb. `Provider.getModels()` returns the current known list — the full catalog for static providers, the last-refreshed list for dynamic ones (llama.cpp, OpenRouter live listing). `refreshModels()` is where dynamic providers fetch.
+
+This split exists because a sync-or-async union (`Promise<T> | T`) invites latent sync assumptions that detonate on the first async provider, while async-only reads force every consumer (UI lists, extension `find`/`getAll` surfaces) through Promises for data that is almost always static. Sync reads + explicit refresh keeps the staleness visible and the contract single: `getModels()` = last known, `refresh()` = make it current. A fetched list is stale the moment it returns anyway; naming the refresh point is honest about it.
+
+Apps own the refresh lifecycle: startup, registry reload, opening a model selector. Freshness-critical lookups are two-step: `await models.refresh("llamacpp"); models.getModel("llamacpp", id)`.
+
+Dynamic refresh must be side-effect-free discovery:
+
+```txt
+OK: fetch /v1/models, enumerate local catalog, refresh cached remote model list
+Not OK: load model, download model, mutate server state, run request probe
+```
+
+Provider-specific model lifecycle (load/unload) belongs in app/provider-management commands, not in `refreshModels()`.
+
+## Streaming path
+
+`Models.stream()` finds the provider by `model.provider`, resolves auth, merges it into request options, and delegates:
+
+```ts
+function stream(model, context, options) {
+  const provider = this.getProvider(model.provider);
+  if (!provider) {
+    // produce an error stream, not a throw — see Error behavior
+  }
+
+  // async setup happens inside the returned stream (lazyStream pattern)
+  const resolution = await this.getAuth(model);
+  const requestModel = resolution?.auth.baseUrl ? { ...model, baseUrl: resolution.auth.baseUrl } : model;
+  const requestOptions = mergeAuth(options, resolution?.auth); // explicit options win per-field
+
+  return provider.stream(requestModel, context, requestOptions);
+}
+```
+
+`stream()` returns `AssistantMessageEventStream` synchronously; async setup (auth resolution, lazy module load) happens inside the returned stream. The forwarding pattern already exists in today's `register-builtins.ts` (`createLazyStream`); extract it as `lazyStream()` in `src/api/lazy.ts`.
+
+No request hot-path model canonicalization: `stream()` uses the supplied model object as-is. If an app wants fresh model metadata, it refreshes the provider and re-reads (`await models.refresh(p); models.getModel(p, id)`) before starting the turn.
+
+## API implementations under `src/api`
+
+An API implementation is reusable stream behavior. It is not a provider.
+
+Uniform export contract — every real implementation module exports exactly:
+
+```ts
+// src/api/anthropic-messages.ts — imports SDKs
+export function stream(model, context, options) { ... }
+export function streamSimple(model, context, options) { ... }
+```
+
+This makes the module itself satisfy `ProviderStreams`, so the lazy wrapper is one generic helper instead of bespoke per-API plumbing. `ProviderStreams` is the untyped dispatch shape (implementation modules export concretely typed functions, which would not be assignable to a generic method); per-API option typing lives on the modules themselves and on `Provider.stream()` via `ApiStreamOptions`:
+
+```ts
+export interface ProviderStreams {
+  stream(model: Model<Api>, context: Context, options?: StreamOptions): AssistantMessageEventStream;
+  streamSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream;
+}
+
+// src/api/lazy.ts
+export function lazyApi(load: () => Promise<ProviderStreams>): ProviderStreams;
+
+// src/api/anthropic-messages.lazy.ts
+export const anthropicMessagesApi = (): ProviderStreams => lazyApi(() => import("./anthropic-messages.ts"));
+```
+
+Import chain:
+
+```txt
+provider module -> lazy API wrapper -> dynamic import(real API impl) -> SDK deps
+```
+
+Notes:
+
+- Bedrock keeps the node-only dynamic import trick (`importNodeOnlyProvider`, `.ts`/`.js` specifier rewrite) inside its lazy wrapper. `setBedrockProviderModule()` (used by the Bun build) moves into the bedrock lazy wrapper module.
+- Shared helper modules (`openai-responses-shared.ts`, `google-shared.ts`, `transform-messages.ts`, prompt-cache, copilot headers) move to `src/api/` alongside the implementations.
+
+## Shared API implementations across concrete providers
+
+Many concrete providers share an API implementation (OpenAI-completions: OpenRouter, Groq, Cerebras, xAI, ZAI, ...). They share lazy API objects by reference:
+
+```ts
+import { openAICompletionsApi } from "../api/openai-completions.lazy.ts";
+
+export function openrouterProvider(): Provider {
+  return createProvider({
+    id: "openrouter",
+    name: "OpenRouter",
+    baseUrl: "https://openrouter.ai/api/v1",
+    auth: { apiKey: envApiKeyAuth("OpenRouter API key", ["OPENROUTER_API_KEY"]) },
+    models: OPENROUTER_MODELS,
+    api: openAICompletionsApi(),
+  });
+}
+```
+
+This copies Vercel AI SDK's useful property: users import concrete providers; shared protocol implementation is internal.
+
+## Auth
+
+Request auth output stays small:
+
+```ts
+export interface ModelAuth {
+  apiKey?: string;
+  headers?: Record<string, string>;
+  baseUrl?: string;
+}
+```
+
+If a value cannot be expressed as `apiKey`, `headers`, or `baseUrl`, it is provider config, not auth (Vertex project/location, Bedrock region/profile, Azure apiVersion are provider factory options).
+
+### Provider auth
+
+`Provider.auth` has exactly two slots; real providers have at most one api-key path and at most one OAuth path, and the slot names carry the UI's oauth-vs-api-key split without a `kind` discriminant or method ids:
+
+```ts
+export interface ProviderAuth {
+  apiKey?: ApiKeyAuth; // stored key/provider env + ambient env/files/ADC/IAM
+  oauth?: OAuthAuth;   // login flow + refresh
+}
+
+export interface ApiKeyAuth {
+  name: string; // "Anthropic API key"
+
+  /** Interactive setup (prompt for key/provider env). Absent = ambient-only (env, ADC, IAM). */
+  login?(callbacks: AuthLoginCallbacks): Promise<ApiKeyCredential>;
+
+  /**
+   * Resolve auth from the stored credential and/or ambient sources, merging
+   * per field (credential.key ?? env("..."), credential.env?.NAME ?? env("...")).
+   * undefined = not configured.
+   */
+  resolve(input: {
+    model: Model<Api>;
+    ctx: AuthContext;
+    credential?: ApiKeyCredential;
+  }): Promise<AuthResult | undefined>;
+}
+
+export interface OAuthAuth {
+  name: string; // "Anthropic (Claude Pro/Max)"
+
+  login(callbacks: AuthLoginCallbacks): Promise<OAuthCredential>;
+
+  /** Exchange the refresh token. Network call; throws on failure (invalid_grant etc.). Runs under the store lock. */
+  refresh(credential: OAuthCredential): Promise<OAuthCredential>;
+
+  /** Side-effect-free derivation of request auth from a valid credential. Covers Copilot-style per-credential baseUrl. Async so lazy wrappers can load the implementation. */
+  toAuth(credential: OAuthCredential): Promise<ModelAuth>;
+}
+
+export interface AuthResult {
+  auth: ModelAuth;
+  /** Human-readable label for status UI: "ANTHROPIC_API_KEY", "OAuth", "~/.aws/credentials". */
+  source?: string;
+}
+
+export interface AuthContext {
+  env(name: string): Promise<string | undefined>;
+  fileExists(path: string): Promise<boolean>; // supports leading ~
+}
+```
+
+The OAuth split (`refresh` + `toAuth` instead of one `resolve`) matches the old `OAuthProviderInterface` (`refreshToken` + `getApiKey`) and lets `Models` own the locking pattern without closure gymnastics: refresh produces a credential, `toAuth` derives request auth from whatever credential ends up stored.
+
+There is no `usesCallbackServer` flag. With `prompt()/notify()` callbacks the flow self-describes at runtime: a flow that runs a callback server issues a `manual_code` prompt racing the server and aborts the prompt when the callback wins. The UI needs no static foreknowledge.
+
+### Credentials
+
+One credential per provider, type-tagged — exactly the shape of today's auth.json (`type: "api_key" | "oauth"` per provider id):
+
+```ts
+export interface ApiKeyCredential {
+  type: "api_key";
+  key?: string;
+  env?: ProviderEnv; // e.g. Cloudflare account/gateway ids, Azure/Vertex/Bedrock scoped config
+}
+
+export interface OAuthCredential extends OAuthCredentials {
+  type: "oauth"; // access, refresh, expires from OAuthCredentials
+}
+
+export type Credential = ApiKeyCredential | OAuthCredential;
+```
+
+`ApiKeyCredential.env` stores provider-scoped environment/config values alongside or instead of a key. `ApiKeyAuth.resolve()` merges per field: `credential.key ?? env("CLOUDFLARE_API_KEY")`, `credential.env?.CLOUDFLARE_ACCOUNT_ID ?? env("CLOUDFLARE_ACCOUNT_ID")`, etc. The credential discriminator intentionally matches today's `auth.json` (`api_key`) so the file-backed store does not need lossy type translation.
+
+### Credential store
+
+The app injects storage; `pi-ai` ships an in-memory default. Keyed by provider id, one credential per provider:
+
+```ts
+export interface CredentialStore {
+  /** Read the stored credential, possibly expired. Display/status use; request auth comes from Models.getAuth(). */
+  read(providerId: string): Promise<Credential | undefined>;
+
+  /**
+   * Serialized write — the only write path. fn sees the current credential
+   * because correct writes (refresh, login-during-refresh) depend on it;
+   * return the new credential, or undefined to leave the entry unchanged.
+   * Mutual exclusion per provider id, cross-process too where the backing
+   * store supports it (file lock). Resolves with the post-write credential.
+   */
+  modify(
+    providerId: string,
+    fn: (current: Credential | undefined) => Promise<Credential | undefined>,
+  ): Promise<Credential | undefined>;
+
+  /** Remove (logout). Serialized against modify. */
+  delete(providerId: string): Promise<void>;
+}
+```
+
+There is deliberately no `set`: an unserialized write path invites read-modify-write races (login-during-refresh clobbering a fresh credential, double token refresh). Call sites:
+
+```ts
+await store.modify(pid, async () => credential);      // login: store this
+await store.read(pid);                                // status UI ("logged in via OAuth")
+await store.delete(pid);                               // logout
+// refresh RMW happens inside Models.getAuth
+```
+
+Error semantics: `read` resolves `undefined` for missing entries; methods reject only on storage failure, and `Models` wraps such rejections in `ModelsError` code `"auth"`. Best-effort stores that serve an in-memory view and record persistence errors internally (today's AuthStorage behavior) are valid implementations.
+
+### Resolution policy (fixed)
+
+`Models.getAuth(model)` is a decision tree, not a loop. A stored credential owns the provider — ambient/env is consulted only when nothing is stored (AuthStorage parity: no silent env fallback after a failed refresh or for an unmatched credential type):
+
+```ts
+const stored = await store.read(provider.id);
+if (stored) {
+  if (stored.type === "oauth" && provider.auth.oauth) {
+    const oauth = provider.auth.oauth;
+    let credential = stored;
+    if (Date.now() >= credential.expires) {                 // optimistic check, lock-free
+      const post = await store.modify(provider.id, async (current) => {
+        if (current?.type !== "oauth") return undefined;    // logged out meanwhile
+        return Date.now() >= current.expires                // authoritative check, under lock
+          ? oauth.refresh(current)                          // throws -> ModelsError("oauth")
+          : undefined;                                      // another process/request refreshed
+      });
+      if (post?.type !== "oauth") return undefined;
+      credential = post;
+    }
+    return { auth: await oauth.toAuth(credential), source: "OAuth" };
+  }
+  if (stored.type === "api_key" && provider.auth.apiKey) {
+    return provider.auth.apiKey.resolve({ model, ctx, credential: stored });
+  }
+  return undefined; // stored credential without matching handler blocks ambient
+}
+return provider.auth.apiKey?.resolve({ model, ctx, credential: undefined }); // ambient
+```
+
+Properties:
+
+- Double-checked locking, same as today's `refreshOAuthTokenWithLock`: valid tokens cost one `read` and zero locks; expired tokens lock, re-check under the lock, refresh once globally, persist before release.
+- Explicit request auth (stream options `apiKey`/`headers`) is merged per-field on top in `stream()`, winning over everything.
+- Refresh failure rejects with `ModelsError("oauth")`; the stored credential is untouched (preserved for retry). Request paths surface this as a stream error with the real cause ("run /login"); status/availability UIs catch the rejection and render "needs re-login" — documented contract on `getAuth`.
+
+### Replacing AuthStorage
+
+The end state for coding-agent: AuthStorage is deleted; its capabilities map onto a `CredentialStore` implementation plus composition.
+
+Today's `getApiKey` priority and its new home:
+
+| AuthStorage today | New design |
+|---|---|
+| runtime override (CLI `--api-key`) | `withRuntimeOverrides(store, overrides)` decorator: `read` returns the override as an `ApiKeyCredential`; never persisted |
+| stored `api_key` (with `$ENV`/`!command` via `resolveConfigValue`) | stored `ApiKeyCredential`; config-value resolution happens at `read` in coding-agent's adapter/decorator (command execution stays app policy) |
+| stored `oauth` + locked refresh, undefined on failure | `getAuth` decision tree above; failure rejects with cause instead of silently unconfiguring |
+| env var (only when nothing stored) | ambient branch of `apiKey.resolve` |
+| `fallbackResolver` (models.json custom providers) | gone — custom providers carry their own `auth.apiKey` |
+
+```txt
+FileCredentialStore        ports AuthStorage's lock backend: read = memory snapshot,
+                           modify = withLockAsync(re-read, fn, merge-write), delete,
+                           internal error recording (drainErrors equivalent)
+└─ withConfigValues        $ENV / !command at read
+   └─ withRuntimeOverrides --api-key
+      └─ createModels({ credentials: store })
+
+login/logout UI            provider.auth.{oauth,apiKey}.login(callbacks) + store.modify/delete
+status UI                  store.read(pid) + getAuth try/catch ("needs /login" on rejection)
+getOAuthProviders          presence of provider.auth.oauth across registered providers
+```
+
+### Login callbacks
+
+One interface serves api-key and OAuth login:
+
+```ts
+export interface AuthLoginCallbacks {
+  /** Aborts the whole login flow. Per-prompt cancellation uses AuthPrompt.signal. */
+  signal?: AbortSignal;
+
+  prompt(prompt: AuthPrompt): Promise<string>;
+  notify(event: AuthEvent): void;
+}
+
+/** `signal` lets the flow cancel a pending prompt when an out-of-band event resolves the step. */
+export type AuthPrompt = { signal?: AbortSignal } & (
+  | { type: "text"; message: string; placeholder?: string }
+  | { type: "secret"; message: string; placeholder?: string }
+  | { type: "select"; message: string; options: readonly { id: string; label: string; description?: string }[] }
+  | { type: "manual_code"; message: string; placeholder?: string }
+);
+
+export type AuthEvent =
+  | { type: "auth_url"; url: string; instructions?: string }
+  | { type: "device_code"; userCode: string; verificationUri: string; intervalSeconds?: number; expiresInSeconds?: number }
+  | { type: "progress"; message: string };
+```
+
+`prompt()` returns the entered/selected string (`select` returns the option id). Flows race a `manual_code` prompt against a callback server by setting `AuthPrompt.signal` and aborting the prompt when the callback wins.
+
+### OAuth attachment
+
+Providers that support OAuth always attach it. There is no factory toggle: the flow is lazy-loaded, so advertising OAuth costs nothing until `login()`/`refresh()` actually runs, and a host that never logs in never loads it.
+
+```ts
+export function anthropicProvider(): Provider {
+  return createProvider({
+    id: "anthropic",
+    name: "Anthropic",
+    baseUrl: "https://api.anthropic.com/v1",
+    auth: {
+      apiKey: envApiKeyAuth("Anthropic API key", ["ANTHROPIC_API_KEY"]),
+      oauth: lazyOAuth({
+        name: "Anthropic (Claude Pro/Max)",
+        load: () => import("../utils/oauth/anthropic.ts").then((m) => m.anthropicOAuth),
+      }),
+    },
+    models: ANTHROPIC_MODELS,
+    api: anthropicMessagesApi(),
+  });
+}
+```
+
+`lazyOAuth()` wraps a dynamically imported `OAuthAuth` so provider definitions can advertise OAuth without importing the implementation (`toAuth` is async for exactly this reason):
+
+```ts
+export function lazyOAuth(input: {
+  name: string;
+  load: () => Promise<OAuthAuth>;
+}): OAuthAuth;
+```
+
+OAuth must not force Node-only code (`node:http`, `node:crypto`) into browser bundles: the dynamic import inside `lazyOAuth()` uses the same bundler-opaque variable-specifier trick as the bedrock lazy wrapper. Browser hosts never trigger the load (no stored node OAuth credentials, no login flow). If web OAuth lands later (sitegeist proved feasibility: Web Crypto PKCE, auth tab, fetch token exchange, device-code polling), it is just a different `OAuthAuth` implementation — no reserved option values.
+
+The existing flows in `src/utils/oauth/` (anthropic, openai-codex, github-copilot) are adapted to `OAuthAuth` (`login`/`refresh`/`toAuth`, replacing `login`/`refreshToken`/`getApiKey`/`modifyModels`) with the new callbacks, staying Node-targeted and lazy-loaded. Copilot's `modifyModels` baseUrl rewriting becomes `toAuth` returning `ModelAuth.baseUrl`.
+
+## Provider wrappers and models.json
+
+`models.json` is a provider wrapper layer. It does not mutate providers in place:
+
+```ts
+function withProviderOverrides(base: Provider, overrides: ProviderOverrides): Provider {
+  return {
+    ...base,
+    name: overrides.name ?? base.name,
+    baseUrl: overrides.baseUrl ?? base.baseUrl,
+    headers: mergeHeaders(base.headers, overrides.headers),
+
+    getModels: () => applyModelOverrides(base.getModels(), overrides.models),
+    refreshModels: base.refreshModels?.bind(base),
+
+    stream: base.stream,
+    streamSimple: base.streamSimple,
+  };
+}
+```
+
+This composes with dynamic providers because `getModels()` delegates to the base source and `refreshModels()` passes through.
+
+Request-auth config from models.json (`$ENV`, `!command`, inline keys) remains app-owned sidecar state, surfaced either as explicit request auth or as a custom `ApiKeyAuth` the app sets on the wrapped provider's `auth.apiKey`.
+
+## Custom providers: createProvider()
+
+One helper builds providers from parts; it handles both single-API and mixed-API providers:
+
+```ts
+export function createProvider(input: {
+  id: string;
+  name?: string;                 // default: id
+  baseUrl?: string;
+  headers?: Record<string, string>;
+  auth: ProviderAuth;            // required, at least one of apiKey/oauth (no "no-auth" providers)
+  /** Initial model list (empty for purely dynamic providers). */
+  models: readonly Model<Api>[];
+  /** Dynamic providers: fetch the current list; createProvider stores it and dedupes in-flight calls. */
+  refreshModels?: () => Promise<readonly Model<Api>[]>;
+  /** Single implementation, or map keyed by model.api for mixed-API providers. */
+  api: ProviderStreams | Record<string, ProviderStreams>;
+}): Provider;
+```
+
+- Single `api`: all models stream through it.
+- Map `api`: `stream()`/`streamSimple()` dispatch on `model.api`; unknown api produces a stream error.
+
+Mixed-API custom providers must be supported (opencode Go/Zen-style providers expose models backed by different APIs under one provider id).
+
+Built-in provider factories use `createProvider()` internally. models.json custom providers map onto it directly:
+
+```json
+{
+  "providers": {
+    "my-openai-proxy": {
+      "api": "openai-completions",
+      "baseUrl": "https://proxy.example/v1",
+      "models": [ ... ]
+    }
+  }
+}
+```
+
+## Compat entrypoint
+
+`@earendil-works/pi-ai/compat` preserves the old global API surface until the coding-agent migration deletes it. New code never imports it.
+
+Old semantics being preserved: global `stream()` can still dispatch by `model.api` through the legacy api-registry for custom providers, mutated models, and tests/extensions that override a built-in API implementation.
+
+- `stream/complete/streamSimple/completeSimple(model, ctx, opts)`: real built-in provider/model/api matches route through a singleton `builtinModels()` collection, so provider auth/env/baseUrl behavior is shared with the new runtime. Unknown providers, mutated models, or overridden API registrations fall back to api-registry dispatch plus `getEnvApiKey` injection.
+- The builtin api registration side effect moves from the root barrel into compat. It skips api ids that already have a registration, since compat may load after a test or extension has already registered an override. `registerApiProvider()/unregisterApiProviders()` keep feeding the compat-local registry; `resetApiProviders()` clears and re-registers builtins.
+- Sync `getModel/getModels/getProviders` are deprecated aliases of `getBuiltinModel/getBuiltinModels/getBuiltinProviders` from `providers/all` (they were always pure generated-catalog reads — verified: nothing ever mutated the old `modelRegistry`).
+- Re-exports the per-API lazy stream wrappers (incl. `setBedrockProviderModule`), `env-api-keys.ts`, and the image-generation registry/catalogs; none of these stay on the root barrel.
+- `export * from "./index.ts"`: compat is a strict superset of the core entrypoint, so consumers switch a file's import path wholesale without symbol surgery.
+
+coding-agent (and the interim agent package) switch imports of these symbols from `@earendil-works/pi-ai` to `@earendil-works/pi-ai/compat` (import-path-only change) and are otherwise untouched until the ModelManager migration.
+
+Extension grace period: the coding-agent extension loader (jiti aliases + Bun `virtualModules`) resolves the `@earendil-works/pi-ai` ROOT specifier to the compat entrypoint. Existing user extensions using the old global API (`complete`, `getModel`, `registerApiProvider`, ...) keep working at runtime without changes; they break only when compat is removed at the ModelManager migration, with a migration guide in the changelog. Typechecking is the nudge: editors resolve the root to the slim core types, so extension sources that typecheck must import old globals from `/compat` — which is what the repo example extensions demonstrate.
+
+## Builtin static helpers
+
+Typed, sync, generated-catalog-only helpers live with the catalogs (exported from `providers/all`):
+
+```ts
+getBuiltinModel(provider, id)   // sync, typed overloads from generated catalog
+getBuiltinModels(provider)      // sync
+getBuiltinProviders()           // sync
+```
+
+Runtime lookup through a `Models` instance is sync over the last-known provider lists: `models.getModel(...)`. Freshness-critical callers run `await models.refresh(provider)` first.
+
+Generated catalogs are split per provider (`providers/<id>.models.ts`) by updating `packages/ai/scripts/generate-models.ts`. If the generator change turns out too large for this pass, splitting may be deferred; `providers/all` and provider factories may temporarily import the monolithic `models.generated.ts`, relying on `sideEffects: false` for pruning.
+
+## Tree-shaking and lazy imports
+
+Rules:
+
+1. Main `@earendil-works/pi-ai` import is core-only.
+2. Provider modules import their catalog, auth helpers, and lazy API wrappers only.
+3. Lazy API wrappers dynamically import real API implementations.
+4. Real API implementations import SDK dependencies.
+5. OAuth implementations are always attached via `lazyOAuth()` and lazy-loaded behind a bundler-opaque dynamic import; provider metadata never eagerly imports Node-only OAuth code.
+6. `providers/all` imports every built-in provider factory and all catalogs. It is the explicit heavy entrypoint.
+7. Provider modules are side-effect-free; importing a provider does not register anything globally.
+8. `package.json` lists only effectful compat/image registration files in `sideEffects`; root and provider modules stay tree-shakeable.
+9. With code splitting, provider SDKs stay in lazy chunks. Without code splitting, bundlers fold statically reachable lazy API implementations into the single bundle; `providers/all` then pulls all statically visible SDKs. Bedrock is the exception because its AWS SDK implementation is behind a bundler-opaque Node-only import and needs `setBedrockProviderModule()` for standalone single-file bundles.
+
+Exports map sketch:
+
+```json
+{
+  "exports": {
+    ".": "./dist/index.js",
+    "./compat": "./dist/compat.js",
+    "./providers/all": "./dist/providers/all.js",
+    "./providers/openai": "./dist/providers/openai.js",
+    "./providers/anthropic": "./dist/providers/anthropic.js",
+    "./providers/*": "./dist/providers/*.js",
+    "./api/*": "./dist/api/*.js"
+  }
+}
+```
+
+Browser smoke check (`scripts/check-browser-smoke.mjs`) must keep passing: bundling the core entrypoint (and any non-node provider entrypoint) must not pull `node:http`/`node:crypto`.
+
+## AgentHarness integration
+
+`AgentHarness` receives a `Models` instance.
+
+- `AgentHarnessOptions.models` is required.
+- The harness does not snapshot `Models` into turn state.
+- Request path calls `this.models.streamSimple(model, context, options)`; same for compaction/branch-summarization paths.
+- Request path never calls async `models.getModel()` to canonicalize; if model metadata needs refresh, the app updates the selected model before starting a turn.
+- Harness tests build `createModels()` and install the faux provider (`fauxProvider()` factory from `providers/faux`).
+
+## coding-agent next phase (not this pass)
+
+coding-agent builds providers in layers and binds them per session:
+
+```txt
+built-in providers (builtinModels)
+-> models.json provider wrappers / custom providers (createProvider)
+-> extension provider wrappers/additions
+```
+
+```ts
+sessionModels.clearProviders();
+for (const provider of layeredProviders) sessionModels.setProvider(provider);
+```
+
+coding-agent owns: `FileCredentialStore` + decorators replacing AuthStorage (see "Replacing AuthStorage"), models.json auth sidecar (`$ENV`, `!command`), command execution policy, provider status labels (from `AuthResult.source`), login/logout UI (driving `auth.{apiKey,oauth}.login()` with `prompt()/notify()`), extension lifecycle, provider-management slash commands.
+
+Current interim state:
+
+- `AgentHarness` already accepts a `Models` instance and uses it for turn streaming, compaction, and branch summaries.
+- coding-agent does not use `AgentHarness` yet; `AgentSession` still drives the low-level `Agent` with a `streamFn`.
+- coding-agent still uses legacy `AuthStorage` + `ModelRegistry` and imports old global pi-ai APIs through `@earendil-works/pi-ai/compat`.
+- The extension loader still aliases the pi-ai root to `/compat` as the runtime grace period for old extensions.
+
+## Implementation TODOs
+
+Check items off as they land. Keep this list current; it is the working state for resumed sessions.
+
+### Phase 1 — core types/runtime
+
+- [x] Rename `types.ts` `Provider` alias to `ProviderId`; fix call sites.
+- [x] Add `ApiOptionsMap` and `ApiStreamOptions<TApi>` to `types.ts` (type-only imports).
+- [x] New `models.ts`: `Provider<TApi>` interface, `hasApi()` guard, `ModelsError` + codes. Auth types live in `src/auth/types.ts` (`ProviderAuth` = `{ apiKey?, oauth? }`, credentials, `CredentialStore` (`read`/`modify`/`delete`, one credential per provider), `AuthResult`, `AuthContext`, `ModelAuth`, login callbacks), in-memory store in `src/auth/credential-store.ts`, default context in `src/auth/context.ts` (browser-safe node:fs trick), `lazyStream()` in `src/api/lazy.ts`.
+- [x] `Models`/`MutableModels`/`createModels({ credentials?, authContext? })` with provider map, sync `getModel(s)` (per-provider failure isolation), explicit async `refresh(provider?)`, `getAuth` (decision tree, double-checked locked refresh), `stream/complete/streamSimple/completeSimple` with per-field auth merge. Tests: `packages/ai/test/models-runtime.test.ts`.
+- [x] Keep metadata helpers: `calculateCost`, `getSupportedThinkingLevels`, `clampThinkingLevel`, `modelsAreEqual`.
+
+### Phase 2 — `src/api/`
+
+- [x] Move stream implementations from `src/providers/` to `src/api/`, renamed by API id (`anthropic.ts` -> `api/anthropic-messages.ts`, etc.).
+- [x] Normalize each implementation module to export exactly `stream` and `streamSimple`.
+- [x] Move shared helpers (`openai-responses-shared`, `google-shared`, `transform-messages`, `openai-prompt-cache`, `github-copilot-headers`, `cloudflare`, `simple-options`) to `src/api/`.
+- [x] Extract `lazyStream()`/`lazyApi()` into `src/api/lazy.ts`.
+- [x] Add `*.lazy.ts` wrappers per API; bedrock keeps node-only import trick and `setBedrockProviderModule()`.
+- [x] Delete `providers/register-builtins.ts`. Interim until Phase 5 compat: builtin api-registry registration lives in `stream.ts`; lazy API wrappers are exported from the root barrel.
+
+### Phase 3 — provider factories + catalogs
+
+- [x] Auth helpers in `src/auth/helpers.ts`: `envApiKeyAuth()` (with secret-prompt `login`), `lazyOAuth()`. OAuth flow loads go through `utils/oauth/load.ts` (bundler-opaque dynamic import); the `OAuthAuth` exports it references land in Phase 4.
+- [x] `createProvider()` in `models.ts` (single + mixed `api` map, dispatch on `model.api`, unknown api -> stream error).
+- [x] Per-provider factories under `src/providers/` for all built-in catalog providers; OAuth attached via `lazyOAuth()` (anthropic, openai-codex, github-copilot); ambient `ApiKeyAuth` for amazon-bedrock (AWS env/profile) and google-vertex (key or ADC+project+location).
+- [x] `providers/all.ts`: `builtinProviders()`, `builtinModels()`, `getBuiltinModel/getBuiltinModels/getBuiltinProviders` re-exports.
+- [x] Faux provider factory (`fauxProvider()` in `providers/faux.ts`) for tests; legacy `registerFauxProvider()` kept until compat dies.
+- [x] Split generated catalogs per provider via `scripts/generate-models.ts` (`providers/<id>.models.ts`); `models.generated.ts` becomes a generated aggregator.
+
+### Phase 4 — OAuth adaptation
+
+- [x] Adapt `utils/oauth/anthropic.ts`, `openai-codex.ts`, `github-copilot.ts` to `OAuthAuth` (`login`/`refresh`/`toAuth`) + `prompt()/notify()`; `modifyModels` baseUrl rewriting becomes `toAuth().baseUrl`. New exports (`anthropicOAuth`, `openaiCodexOAuth`, `githubCopilotOAuth`) sit next to the old `OAuthProviderInterface` objects, which survive until Phase 7.
+- [x] No `usesCallbackServer` on `OAuthAuth`: callback-server flows race a `manual_code` prompt (aborted via `AuthPrompt.signal` once the flow settles). The old interface keeps its flag until it dies with compat.
+
+### Phase 5 — packaging
+
+- [x] `index.ts` core-only and side-effect free (no catalogs, no provider factories, no api-registry, no env-api-keys, no images, no OAuth, no compat). Typed catalog reads (`getBuiltin*`) implemented in `providers/all.ts`; `models.ts` no longer imports `models.generated.ts`.
+- [x] `compat.ts`: superset of index + old api-dispatch globals, deprecated `getModel/getModels/getProviders` aliases, lazy api wrappers + `setBedrockProviderModule`, `getEnvApiKey`, images. Registration side effect lives here (skip-if-present).
+- [x] Subpath exports map (`./compat`, `./providers/*`, `./api/*`); `sideEffects` array listing the effectful modules (`compat`, images registration) instead of `false`.
+- [x] Browser smoke (entry now imports old globals from `/compat`) + shrinkwrap checks green. Internal old-global imports switched to `/compat` already (42 files in agent/coding-agent/examples; vitest configs alias `/compat` to src; spawn-CLI tests resolve workspace dist, so `packages/ai` + `packages/agent` dists were rebuilt).
+
+### Phase 6 — AgentHarness
+
+- [x] `AgentHarnessOptions.models` required (`readonly models` on the harness); the harness stream path uses `models.streamSimple()`. `StreamFn` redefined structurally (no compat type dependency); `Models.streamSimple` satisfies it.
+- [x] Compaction/branch-summarization take the harness `Models` instance. `getApiKeyAndHeaders` is removed entirely — `Models` is the only auth path; per-request key resolution becomes provider auth on the collection. `compact()`/`generateSummary()`/`generateBranchSummary()` lose their explicit `apiKey`/`headers` parameters.
+- [x] Harness tests use `createModels()` + `fauxProvider()` with unique per-fake provider ids; no global api-registry state, no unregister bookkeeping.
+
+### Phase 7 — coding-agent bridge (minimal)
+
+- [x] Switch old-global imports to `@earendil-works/pi-ai/compat` (landed with Phase 5; compat is a superset so the switch was path-only). Extension loader resolves the pi-ai root to compat as the runtime grace period.
+- [x] Everything else originally sketched here is gated on coding-agent actually streaming through a `Models` instance — coding-agent's `AgentSession` drives the low-level `Agent` via `streamFn`, not the harness — and moved to Phase 9.
+
+### Phase 8 — wrap-up
+
+- [x] Update/add tests; run affected suites (tests landed with each phase; `./test.sh` green throughout).
+- [x] `packages/ai/CHANGELOG.md`: `### Breaking Changes` with migration guide (compat entrypoint, `Provider` -> `ProviderId`, api module moves) + `### Added` for the new Models/provider/auth API.
+- [x] `packages/coding-agent/CHANGELOG.md`: `### Changed` entry for extension authors — runtime unaffected (loader resolves the pi-ai root to compat), typecheck nudges to `/compat` or the new API; removal happens later with a migration guide.
+- [x] `packages/agent/CHANGELOG.md`: `### Breaking Changes` for required `AgentHarnessOptions.models`, compaction signature changes, structural `StreamFn`.
+- [x] `npm run check` clean.
+
+### Phase 9 — coding-agent on Models + CredentialStore (in scope)
+
+coding-agent replaces AuthStorage and ModelRegistry's internals with `FileCredentialStore` + a `MutableModels` collection. AgentSession itself stays (AgentHarness adoption is pi 2.0); only its model/auth substrate swaps. Layering is strictly one-directional:
+
+```txt
+FileCredentialStore (auth.json, locked, $ENV/!command resolution) + explicit --api-key overlay
+        ↑
+MutableModels: builtin factories (wrapped per models.json config) + custom providers (models.json ∪ extensions)
+        ↑
+ModelRegistry: compatibility facade — sync last-known reads delegate to the collection; registerProvider/login/logout/status for extensions + UI
+        ↑
+AgentSession / sdk / interactive-mode (stream via models; await only auth/refresh paths)
+```
+
+Decisions:
+
+- `AuthStorage` is deleted as a type — it would otherwise depend on provider auth while provider auth depends on its store (circular). Its surface splits: `get`/`set`/`remove` -> `CredentialStore`; `getApiKey` -> `Models.getAuth`; `login`/`logout`/`getAuthStatus` -> ModelRegistry facade methods over `provider.auth.oauth` + the store.
+- `FileCredentialStore` is self-contained (path, locking, parse/write, chmod, error buffering) and owns `auth.json` semantics, including `$ENV`/`!command` resolution for stored API-key credentials. Persisted values stay raw; resolution returns copies for auth use.
+- Runtime `--api-key` overrides are an explicit store overlay (an override reads as an ephemeral stored api-key credential, masking stored OAuth — matches today's priority). Every registered provider is guaranteed an `apiKey` auth slot so overrides apply to OAuth-only providers too.
+- `ModelRegistry.getAll`/`find`/`getAvailable` stay sync for SDK and extension compatibility, delegating to the collection's last-known sync model lists and fast configured-looking status checks. Dynamic providers update through explicit async `refresh()`, and request auth remains async through `getApiKeyAndHeaders()`/`Models.getAuth()`. Extensions also get the collection itself as the forward API.
+- models.json keeps FULL feature parity, implemented as provider decoration: builtin factories wrapped so `getModels()` applies provider `baseUrl`/`compat` overlays, `modelOverrides`, and custom-model merges (async-safe); provider `apiKey`/`headers`/`authHeader` configs become that provider's `ApiKeyAuth` (config first, factory auth fallback); parse errors keep `getError()` semantics.
+- Extension `ProviderConfig` parity: provider-keyed `streamSimple`, old-style `oauth` adapted to `OAuthAuth` (`modifyModels` -> `getModels` wrap + `toAuth`), full model replacement per provider. Legacy `registerApiProvider` writes stay compat-local for consumers that call global `complete()`; they die with compat.
+- Copilot: stored-credential baseUrl applied in the wrapped `getModels()` (extension-visible models stay correct) plus per-request `toAuth().baseUrl`.
+- Cloudflare: provider-auth substitution (key + `CLOUDFLARE_ACCOUNT_ID`/`CLOUDFLARE_GATEWAY_ID` from credential `env` or ambient `AuthContext.env()` -> `ModelAuth.baseUrl`). Built-in compat calls route through `Models`, so they use the same provider auth path.
+
+Ordering for new sessions:
+
+1. [x] pi-ai rework first: `Provider.getModels()` sync + optional `refreshModels()`; `Models.getModels`/`getModel` sync, `Models.refresh(provider?)` async; `createProvider` takes `models` array + optional `refreshModels` fetcher (in-flight dedupe). Reverses Phase 1's async-listing decision — see "Provider model listing" for rationale (sync-or-async unions breed latent sync assumptions; async-only breaks sync consumer surfaces like extension `find`/`getAll`).
+2. [x] Cloudflare provider auth in pi-ai factories: Workers AI and AI Gateway validate their required account/gateway env/config and return resolved `baseUrl`, provider-scoped env, and header suppression/override metadata from provider auth.
+3. [ ] Add `FileCredentialStore` in coding-agent.
+   - Implement the pi-ai `CredentialStore` interface as a self-contained `auth.json` store; do not depend on the old `AuthStorageBackend` abstraction, though its lock/retry semantics may be ported.
+   - Preserve the existing file format. `ApiKeyCredential` uses `{ type: "api_key", key?, env? }`, matching today's `auth.json`; do not translate `env` into metadata or rewrite discriminators.
+   - Resolve `$ENV`/`!command` in stored API-key `key` and `env` values out of the box using an injected execution/config environment. `$ENV` lookup should come from that environment, and `!command` should run through the shared shell execution path rather than direct `execSync`.
+   - Persist raw config values; resolved credentials returned for auth use must be copies and must not rewrite `$ENV`/`!command` strings unless a caller explicitly stores new values.
+   - `read(provider)` returns the current credential snapshot and records parse/storage errors for status UI parity.
+   - `modify(provider, fn)` must lock, re-read, run `fn`, merge-write the provider entry, chmod `0600`, and return the post-write credential.
+   - `delete(provider)` must lock and remove only that provider's entry.
+   - Add file-backed and in-memory tests covering lock/RMW behavior, `api_key` reads with config-value resolution, OAuth reads, provider `env` preservation, delete, parse errors, and concurrent refresh-style modifications.
+4. [ ] Add runtime override overlay for coding-agent policy.
+   - `withRuntimeOverrides(store, overrides)` implements CLI `--api-key`: read returns an ephemeral `{ type: "api_key", key }` for each overridden provider, masking stored OAuth/API credentials without persisting.
+   - Runtime overrides must apply even to OAuth-capable providers; every provider registered in coding-agent must retain or gain an `apiKey` auth slot so the overlay is meaningful.
+   - Tests cover precedence: runtime override > stored credential > models.json config auth > ambient provider env, with stored credential blocking ambient fallback.
+5. [ ] Build provider decoration helpers for `models.json`.
+   - Start from built-in provider factories, not generated model arrays.
+   - Wrap provider `getModels()` so provider-level `baseUrl`/`headers`/`compat`, per-model `modelOverrides`, and custom model merges apply on every sync read.
+   - Preserve `refreshModels()` passthrough so dynamic providers compose with decorations.
+   - Convert provider `apiKey`/`headers`/`authHeader` models.json config into a wrapped `ApiKeyAuth` that resolves config values first and falls back to the base provider auth.
+   - Custom providers with `models` use `createProvider()` with the appropriate lazy API wrapper or extension-provided stream implementation.
+   - Parse errors must keep current `ModelRegistry.getError()` behavior: built-ins remain available, and the error is visible.
+6. [ ] Copilot `getModels()` baseUrl wrap.
+   - GitHub Copilot OAuth `toAuth()` already returns per-credential request `baseUrl` for streaming.
+   - Wrap Copilot's provider `getModels()` when an OAuth credential is present so extension/UI-visible model metadata also carries the authenticated account base URL.
+   - Keep API-key/env-token Copilot behavior unchanged.
+   - Add tests for model metadata before login, after OAuth credential, after refresh/baseUrl change, and logout.
+7. [ ] Extension OAuth adapter.
+   - Adapt old extension `OAuthProviderInterface` configs to pi-ai `OAuthAuth`.
+   - `login` maps old callbacks/events to `prompt()/notify()`.
+   - `refreshToken` maps to `refresh`.
+   - `getApiKey` maps to `toAuth`.
+   - `modifyModels` becomes a provider `getModels()` wrapper plus `toAuth().baseUrl` where applicable.
+   - Preserve existing extension runtime compatibility through the `/compat` alias until Phase 10.
+8. [ ] Rebuild coding-agent `ModelRegistry` over `MutableModels`.
+   - It owns a `MutableModels` instance built from decorated built-ins + models.json custom providers + extension providers.
+   - `getAll()`, `find()`, and `getAvailable()` remain sync compatibility methods over last-known model lists and fast configured-looking auth status. Do not break the extension-facing `modelRegistry` surface for these reads.
+   - `refresh()` is the explicit async freshness boundary: rebuild provider layers and call `models.refresh()` where needed; no global api-registry reset should be part of the new path except compat-only grace behavior.
+   - `registerProvider()`/`unregisterProvider()` mutate provider layers and rebuild the collection.
+   - Facade auth ops (`login`, `logout`, provider status, available OAuth providers) drive `provider.auth.{apiKey,oauth}` and the `CredentialStore`; no `AuthStorage` type remains.
+   - Legacy `registerApiProvider` writes stay only for `/compat` callers and are removed in Phase 10.
+9. [ ] Rewire consumers.
+   - `AgentSession` stream function resolves through `ModelRegistry`/`Models`, not `getApiKeyAndHeaders()` + compat globals.
+   - SDK options replace `authStorage` with `credentials?: CredentialStore` or an agent-dir-backed default; update `sdk.md` and examples.
+   - `model-resolver`, `--list-models`, model selector, login/logout/status UI, and provider attribution use sync last-known model reads and await only explicit refresh/auth operations.
+   - CLI `--api-key` populates the runtime override decorator instead of mutating `AuthStorage`.
+   - Keep extension loader root-to-compat alias until Phase 10, but expose the new collection/facade as the forward API.
+10. [ ] Test migration and real-provider validation.
+    - Unit tests for `FileCredentialStore`, runtime override overlay, provider decoration, extension OAuth adapter, Models-backed ModelRegistry facade, and consumer rewiring.
+    - Regression tests for Cloudflare account/gateway env, Copilot OAuth baseUrl wrapping, runtime `--api-key` precedence, `$ENV`/`!command` resolution, and stored credential blocking ambient fallback.
+    - Update existing tests for sync last-known `ModelRegistry.getAll/find/getAvailable` plus explicit async refresh behavior.
+    - Run targeted non-e2e suites plus tmux validation of login flows against real providers (Anthropic OAuth/API key, OpenAI Codex OAuth, GitHub Copilot OAuth, Cloudflare AI Gateway, Bedrock if credentials are available).
+
+### Phase 10 — compat deletion (pi 2.0 era, separate)
+
+- [ ] AgentSession -> AgentHarness; the registry facade dies in favor of harness `Models`.
+- [ ] Move ALL internal `/compat` imports to the new API: every package's src, all tests, and the example extensions (examples then demonstrate the new API). Nothing inside the repo may import `/compat` at that point.
+- [ ] Delete `/compat`, `env-api-keys.ts`, the extension-loader root-to-compat alias, the old `pi-ai/oauth` registry and `OAuthProviderInterface` (incl. `usesCallbackServer`), and the compat-local legacy API registry. This is the extension-author breaking release; changelog carries the migration guide.
+
+### Deferred / follow-ups
+
+- [ ] Web OAuth implementations (sitegeist-style) as an alternative `OAuthAuth`.
+- [x] Images API redesign: `ImagesModels`/`ImagesProvider`/`createImagesProvider` mirror the chat-side design (sync reads, explicit refresh, never-reject generation); auth resolution shared with the chat side via the free-standing `resolveProviderAuth()` in `auth/resolve.ts` (which also owns `ModelsError`; both collections pass their store/context as arguments — no resolver object). `openrouterImagesProvider()` factory + `builtinImagesProviders()`/`builtinImagesModels()` in `providers/all`; impl moved to `api/openrouter-images.ts` with a lazy wrapper. The old global image API (registry + `getImageModel*` + `generateImages`) stays on compat; `ImagesProvider` id alias in types.ts renamed to `ImagesProviderId` (mirror of `Provider` -> `ProviderId`).
+
+## Error behavior
+
+`undefined` means not found or not configured. Real failures reject or become stream errors.
+
+```ts
+export type ModelsErrorCode =
+  | "model_source"      // provider model refresh failed
+  | "model_validation"  // model object invalid
+  | "provider"          // unknown provider, dispatch failure
+  | "stream"            // stream setup failure
+  | "auth"              // auth resolution failure
+  | "oauth";            // oauth login/refresh failure
+```
+
+- `Models.stream()` produces stream errors (error event + error result) for async setup failures; it does not throw after returning the stream.
+- `Models.getModels()` is a sync best-effort read: a provider whose `getModels()` throws yields no models. `Models.refresh(provider)` rejects on that provider's fetch failure; `Models.refresh()` (all providers) is concurrent best-effort. Apps that need a concrete listing failure refresh the single provider.
+- Auth resolution and credential store failures reject loudly (`ModelsError` codes `auth`/`oauth`); silent fallback to a different auth path after a failure risks billing surprises. A stored credential always blocks ambient/env fallback, including after a failed refresh.
+- Status/availability UIs catch `getAuth` rejections and render "needs re-login"; they do not treat rejection as "unconfigured".

packages/agent/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@earendil-works/pi-agent-core",
-	"version": "0.79.10",
+	"version": "0.80.3",
 	"description": "General-purpose agent with transport abstraction, state management, and attachment support",
 	"type": "module",
 	"main": "./dist/index.js",
@@ -10,10 +10,6 @@
 			"types": "./dist/index.d.ts",
 			"import": "./dist/index.js"
 		},
-		"./base": {
-			"types": "./dist/base.d.ts",
-			"import": "./dist/base.js"
-		},
 		"./node": {
 			"types": "./dist/node.d.ts",
 			"import": "./dist/node.js"
@@ -33,7 +29,7 @@
 		"prepublishOnly": "npm run clean && npm run build"
 	},
 	"dependencies": {
-		"@earendil-works/pi-ai": "^0.79.10",
+		"@earendil-works/pi-ai": "^0.80.3",
 		"ignore": "7.0.5",
 		"typebox": "1.1.38",
 		"yaml": "2.9.0"

packages/agent/src/agent-loop.ts

@@ -10,7 +10,7 @@ import {
 	streamSimple,
 	type ToolResultMessage,
 	validateToolArguments,
-} from "@earendil-works/pi-ai/base";
+} from "@earendil-works/pi-ai/compat";
 import type {
 	AgentContext,
 	AgentEvent,
@@ -205,7 +205,13 @@ async function runLoop(
 			const toolResults: ToolResultMessage[] = [];
 			hasMoreToolCalls = false;
 			if (toolCalls.length > 0) {
-				const executedToolBatch = await executeToolCalls(currentContext, message, config, signal, emit);
+				// A "length" stop means the output was cut off by the token limit, so
+				// every tool call in the message may carry truncated arguments. Fail
+				// them all instead of executing potentially borked calls.
+				const executedToolBatch =
+					message.stopReason === "length"
+						? await failToolCallsFromTruncatedMessage(toolCalls, emit)
+						: await executeToolCalls(currentContext, message, config, signal, emit);
 				toolResults.push(...executedToolBatch.messages);
 				hasMoreToolCalls = !executedToolBatch.terminate;
 
@@ -367,6 +373,40 @@ async function streamAssistantResponse(
 	return finalMessage;
 }
 
+/**
+ * Fail all tool calls from an assistant message that was truncated by the
+ * output token limit. Streamed tool-call arguments are finalized with a
+ * best-effort JSON salvage parser, so a truncated message can yield tool calls
+ * whose arguments parse and validate but are silently incomplete. None of them
+ * are safe to execute; report each as an error so the model can re-issue them.
+ */
+async function failToolCallsFromTruncatedMessage(
+	toolCalls: AgentToolCall[],
+	emit: AgentEventSink,
+): Promise<ExecutedToolCallBatch> {
+	const messages: ToolResultMessage[] = [];
+	for (const toolCall of toolCalls) {
+		await emit({
+			type: "tool_execution_start",
+			toolCallId: toolCall.id,
+			toolName: toolCall.name,
+			args: toolCall.arguments,
+		});
+		const finalized: FinalizedToolCallOutcome = {
+			toolCall,
+			result: createErrorToolResult(
+				`Tool call "${toolCall.name}" was not executed: the response hit the output token limit, so its arguments may be truncated. Re-issue the tool call with complete arguments.`,
+			),
+			isError: true,
+		};
+		await emitToolExecutionEnd(finalized, emit);
+		const toolResultMessage = createToolResultMessage(finalized);
+		await emitToolResultMessage(toolResultMessage, emit);
+		messages.push(toolResultMessage);
+	}
+	return { messages, terminate: false };
+}
+
 /**
  * Execute tool calls from an assistant message.
  */
@@ -735,7 +775,9 @@ function createToolResultMessage(finalized: FinalizedToolCallOutcome): ToolResul
 		role: "toolResult",
 		toolCallId: finalized.toolCall.id,
 		toolName: finalized.toolCall.name,
-		content: finalized.result.content,
+		// Untyped tools (JS extensions) can return results without content; normalize
+		// so the null never enters session history or provider payloads.
+		content: finalized.result.content ?? [],
 		details: finalized.result.details,
 		isError: finalized.isError,
 		timestamp: Date.now(),

packages/agent/src/agent.ts

@@ -7,7 +7,7 @@ import {
 	type TextContent,
 	type ThinkingBudgets,
 	type Transport,
-} from "@earendil-works/pi-ai/base";
+} from "@earendil-works/pi-ai/compat";
 import { runAgentLoop, runAgentLoopContinue } from "./agent-loop.ts";
 import type {
 	AfterToolCallContext,
@@ -21,6 +21,7 @@ import type {
 	AgentTool,
 	BeforeToolCallContext,
 	BeforeToolCallResult,
+	PrepareNextTurnContext,
 	QueueMode,
 	StreamFn,
 	ToolExecutionMode,
@@ -106,6 +107,10 @@ export interface AgentOptions {
 	prepareNextTurn?: (
 		signal?: AbortSignal,
 	) => Promise<AgentLoopTurnUpdate | undefined> | AgentLoopTurnUpdate | undefined;
+	prepareNextTurnWithContext?: (
+		context: PrepareNextTurnContext,
+		signal?: AbortSignal,
+	) => Promise<AgentLoopTurnUpdate | undefined> | AgentLoopTurnUpdate | undefined;
 	steeringMode?: QueueMode;
 	followUpMode?: QueueMode;
 	sessionId?: string;
@@ -186,6 +191,10 @@ export class Agent {
 	public prepareNextTurn?: (
 		signal?: AbortSignal,
 	) => Promise<AgentLoopTurnUpdate | undefined> | AgentLoopTurnUpdate | undefined;
+	public prepareNextTurnWithContext?: (
+		context: PrepareNextTurnContext,
+		signal?: AbortSignal,
+	) => Promise<AgentLoopTurnUpdate | undefined> | AgentLoopTurnUpdate | undefined;
 	private activeRun?: ActiveRun;
 	/** Session identifier forwarded to providers for cache-aware backends. */
 	public sessionId?: string;
@@ -209,6 +218,7 @@ export class Agent {
 		this.beforeToolCall = options.beforeToolCall;
 		this.afterToolCall = options.afterToolCall;
 		this.prepareNextTurn = options.prepareNextTurn;
+		this.prepareNextTurnWithContext = options.prepareNextTurnWithContext;
 		this.steeringQueue = new PendingMessageQueue(options.steeringMode ?? "one-at-a-time");
 		this.followUpQueue = new PendingMessageQueue(options.followUpMode ?? "one-at-a-time");
 		this.sessionId = options.sessionId;
@@ -433,7 +443,15 @@ export class Agent {
 			toolExecution: this.toolExecution,
 			beforeToolCall: this.beforeToolCall,
 			afterToolCall: this.afterToolCall,
-			prepareNextTurn: this.prepareNextTurn ? async () => await this.prepareNextTurn?.(this.signal) : undefined,
+			prepareNextTurn:
+				this.prepareNextTurnWithContext || this.prepareNextTurn
+					? async (context) => {
+							if (this.prepareNextTurnWithContext) {
+								return await this.prepareNextTurnWithContext(context, this.signal);
+							}
+							return await this.prepareNextTurn?.(this.signal);
+						}
+					: undefined,
 			convertToLlm: this.convertToLlm,
 			transformContext: this.transformContext,
 			getApiKey: this.getApiKey,

packages/agent/src/base.ts

@@ -1,39 +0,0 @@
-export * from "./agent.ts";
-export * from "./agent-loop.ts";
-export * from "./harness/agent-harness.ts";
-export {
-	type BranchPreparation,
-	type BranchSummaryDetails,
-	type CollectEntriesResult,
-	collectEntriesForBranchSummary,
-	generateBranchSummary,
-	prepareBranchEntries,
-} from "./harness/compaction/branch-summarization.ts";
-export {
-	calculateContextTokens,
-	compact,
-	DEFAULT_COMPACTION_SETTINGS,
-	estimateContextTokens,
-	estimateTokens,
-	findCutPoint,
-	findTurnStartIndex,
-	generateSummary,
-	getLastAssistantUsage,
-	prepareCompaction,
-	serializeConversation,
-	shouldCompact,
-} from "./harness/compaction/compaction.ts";
-export * from "./harness/messages.ts";
-export * from "./harness/prompt-templates.ts";
-export * from "./harness/session/jsonl-repo.ts";
-export * from "./harness/session/memory-repo.ts";
-export * from "./harness/session/repo-utils.ts";
-export * from "./harness/session/session.ts";
-export { uuidv7 } from "./harness/session/uuid.ts";
-export * from "./harness/skills.ts";
-export * from "./harness/system-prompt.ts";
-export * from "./harness/types.ts";
-export * from "./harness/utils/shell-output.ts";
-export * from "./harness/utils/truncate.ts";
-export * from "./proxy.ts";
-export * from "./types.ts";

packages/agent/src/harness/agent-harness.ts

@@ -1,10 +1,4 @@
-import {
-	type AssistantMessage,
-	type ImageContent,
-	type Model,
-	streamSimple,
-	type UserMessage,
-} from "@earendil-works/pi-ai/base";
+import type { AssistantMessage, ImageContent, Model, Models, UserMessage } from "@earendil-works/pi-ai";
 import { runAgentLoop } from "../agent-loop.ts";
 import type {
 	AgentContext,
@@ -75,17 +69,6 @@ function cloneStreamOptions(streamOptions?: AgentHarnessStreamOptions): AgentHar
 	};
 }
 
-function mergeHeaders(...headers: Array<Record<string, string> | undefined>): Record<string, string> | undefined {
-	const merged: Record<string, string> = {};
-	let hasHeaders = false;
-	for (const entry of headers) {
-		if (!entry) continue;
-		Object.assign(merged, entry);
-		hasHeaders = true;
-	}
-	return hasHeaders ? merged : undefined;
-}
-
 function findDuplicateNames(names: string[]): string[] {
 	const seen = new Set<string>();
 	const duplicates = new Set<string>();
@@ -178,6 +161,7 @@ export class AgentHarness<
 > {
 	readonly env: ExecutionEnv;
 	private session: Session;
+	readonly models: Models;
 	private phase: AgentHarnessPhase = "idle";
 	private runAbortController?: AbortController;
 	private runPromise?: Promise<void>;
@@ -186,7 +170,6 @@ export class AgentHarness<
 	private thinkingLevel: ThinkingLevel;
 	private systemPrompt: AgentHarnessOptions<TSkill, TPromptTemplate, TTool>["systemPrompt"];
 	private streamOptions: AgentHarnessStreamOptions;
-	private getApiKeyAndHeaders?: AgentHarnessOptions["getApiKeyAndHeaders"];
 	private resources: AgentHarnessResources<TSkill, TPromptTemplate>;
 	private tools = new Map<string, TTool>();
 	private activeToolNames: string[];
@@ -200,10 +183,10 @@ export class AgentHarness<
 	constructor(options: AgentHarnessOptions<TSkill, TPromptTemplate, TTool>) {
 		this.env = options.env;
 		this.session = options.session;
+		this.models = options.models;
 		this.resources = options.resources ?? {};
 		this.streamOptions = cloneStreamOptions(options.streamOptions);
 		this.systemPrompt = options.systemPrompt;
-		this.getApiKeyAndHeaders = options.getApiKeyAndHeaders;
 		this.validateUniqueNames(
 			(options.tools ?? []).map((tool) => tool.name),
 			"Duplicate tool name(s)",
@@ -376,13 +359,9 @@ export class AgentHarness<
 	private createStreamFn(getTurnState: () => AgentHarnessTurnState<TSkill, TPromptTemplate, TTool>): StreamFn {
 		return async (model, context, streamOptions) => {
 			const turnState = getTurnState();
-			const auth = await this.getApiKeyAndHeaders?.(model);
-			const snapshotOptions: AgentHarnessStreamOptions = {
-				...turnState.streamOptions,
-				headers: mergeHeaders(turnState.streamOptions.headers, auth?.headers),
-			};
+			const snapshotOptions: AgentHarnessStreamOptions = { ...turnState.streamOptions };
 			const requestOptions = await this.emitBeforeProviderRequest(model, turnState.sessionId, snapshotOptions);
-			return streamSimple(model, context, {
+			return this.models.streamSimple(model, context, {
 				cacheRetention: requestOptions.cacheRetention,
 				headers: requestOptions.headers,
 				maxRetries: requestOptions.maxRetries,
@@ -401,7 +380,6 @@ export class AgentHarness<
 				sessionId: turnState.sessionId,
 				timeoutMs: requestOptions.timeoutMs,
 				transport: requestOptions.transport,
-				apiKey: auth?.apiKey,
 			});
 		};
 	}
@@ -713,8 +691,6 @@ export class AgentHarness<
 		try {
 			const model = this.model;
 			if (!model) throw new AgentHarnessError("invalid_state", "No model set for compaction");
-			const auth = await this.getApiKeyAndHeaders?.(model);
-			if (!auth) throw new AgentHarnessError("auth", "No auth available for compaction");
 			const branchEntries = await this.session.getBranch();
 			const preparationResult = prepareCompaction(branchEntries, DEFAULT_COMPACTION_SETTINGS);
 			if (!preparationResult.ok) throw preparationResult.error;
@@ -731,15 +707,7 @@ export class AgentHarness<
 			const provided = hookResult?.compaction;
 			const compactResult = provided
 				? { ok: true as const, value: provided }
-				: await compact(
-						preparation,
-						model,
-						auth.apiKey,
-						auth.headers,
-						customInstructions,
-						undefined,
-						this.thinkingLevel,
-					);
+				: await compact(preparation, this.models, model, customInstructions, undefined, this.thinkingLevel);
 			if (!compactResult.ok) throw compactResult.error;
 			const result = compactResult.value;
 			const entryId = await this.session.appendCompaction(
@@ -792,12 +760,9 @@ export class AgentHarness<
 			if (!summaryText && options?.summarize && entries.length > 0) {
 				const model = this.model;
 				if (!model) throw new AgentHarnessError("invalid_state", "No model set for branch summary");
-				const auth = await this.getApiKeyAndHeaders?.(model);
-				if (!auth) throw new AgentHarnessError("auth", "No auth available for branch summary");
 				const branchSummary = await generateBranchSummary(entries, {
+					models: this.models,
 					model,
-					apiKey: auth.apiKey,
-					headers: auth.headers,
 					signal: new AbortController().signal,
 					customInstructions: hookResult?.customInstructions ?? options?.customInstructions,
 					replaceInstructions: hookResult?.replaceInstructions ?? options?.replaceInstructions,

packages/agent/src/harness/compaction/branch-summarization.ts

@@ -1,4 +1,5 @@
-import { completeSimple, type Model } from "@earendil-works/pi-ai/base";
+import type { Model, Models } from "@earendil-works/pi-ai";
+
 import type { AgentMessage } from "../../types.ts";
 import {
 	convertToLlm,
@@ -48,12 +49,10 @@ export interface CollectEntriesResult {
 
 /** Options for generating a branch summary. */
 export interface GenerateBranchSummaryOptions {
+	/** Provider collection the summarization request goes through; owns auth resolution. */
+	models: Models;
 	/** Model used for summarization. */
 	model: Model<any>;
-	/** API key forwarded to the provider. */
-	apiKey: string;
-	/** Optional request headers forwarded to the provider. */
-	headers?: Record<string, string>;
 	/** Abort signal for the summarization request. */
 	signal: AbortSignal;
 	/** Optional instructions appended to or replacing the default prompt. */
@@ -201,7 +200,7 @@ export async function generateBranchSummary(
 	entries: SessionTreeEntry[],
 	options: GenerateBranchSummaryOptions,
 ): Promise<Result<BranchSummaryResult, BranchSummaryError>> {
-	const { model, apiKey, headers, signal, customInstructions, replaceInstructions, reserveTokens = 16384 } = options;
+	const { models, model, signal, customInstructions, replaceInstructions, reserveTokens = 16384 } = options;
 	const contextWindow = model.contextWindow || 128000;
 	const tokenBudget = contextWindow - reserveTokens;
 
@@ -229,10 +228,10 @@ export async function generateBranchSummary(
 			timestamp: Date.now(),
 		},
 	];
-	const response = await completeSimple(
+	const response = await models.completeSimple(
 		model,
 		{ systemPrompt: SUMMARIZATION_SYSTEM_PROMPT, messages: summarizationMessages },
-		{ apiKey, headers, signal, maxTokens: 2048 },
+		{ signal, maxTokens: 2048 },
 	);
 	if (response.stopReason === "aborted") {
 		return err(new BranchSummaryError("aborted", response.errorMessage || "Branch summary aborted"));

packages/agent/src/harness/compaction/compaction.ts

@@ -1,11 +1,4 @@
-import {
-	type AssistantMessage,
-	completeSimple,
-	type ImageContent,
-	type Model,
-	type TextContent,
-	type Usage,
-} from "@earendil-works/pi-ai/base";
+import type { AssistantMessage, ImageContent, Model, Models, TextContent, Usage } from "@earendil-works/pi-ai";
 import type { AgentMessage, ThinkingLevel } from "../../types.ts";
 import {
 	convertToLlm,
@@ -128,14 +121,19 @@ export function calculateContextTokens(usage: Usage): number {
 function getAssistantUsage(msg: AgentMessage): Usage | undefined {
 	if (msg.role === "assistant" && "usage" in msg) {
 		const assistantMsg = msg as AssistantMessage;
-		if (assistantMsg.stopReason !== "aborted" && assistantMsg.stopReason !== "error" && assistantMsg.usage) {
+		if (
+			assistantMsg.stopReason !== "aborted" &&
+			assistantMsg.stopReason !== "error" &&
+			assistantMsg.usage &&
+			calculateContextTokens(assistantMsg.usage) > 0
+		) {
 			return assistantMsg.usage;
 		}
 	}
 	return undefined;
 }
 
-/** Return usage from the last successful assistant message in session entries. */
+/** Return usage from the last valid assistant message in session entries. */
 export function getLastAssistantUsage(entries: SessionTreeEntry[]): Usage | undefined {
 	for (let i = entries.length - 1; i >= 0; i--) {
 		const entry = entries[i];
@@ -461,10 +459,9 @@ Keep each section concise. Preserve exact file paths, function names, and error
 /** Generate or update a conversation summary for compaction. */
 export async function generateSummary(
 	currentMessages: AgentMessage[],
+	models: Models,
 	model: Model<any>,
 	reserveTokens: number,
-	apiKey: string,
-	headers?: Record<string, string>,
 	signal?: AbortSignal,
 	customInstructions?: string,
 	previousSummary?: string,
@@ -496,10 +493,10 @@ export async function generateSummary(
 
 	const completionOptions =
 		model.reasoning && thinkingLevel && thinkingLevel !== "off"
-			? { maxTokens, signal, apiKey, headers, reasoning: thinkingLevel }
-			: { maxTokens, signal, apiKey, headers };
+			? { maxTokens, signal, reasoning: thinkingLevel }
+			: { maxTokens, signal };
 
-	const response = await completeSimple(
+	const response = await models.completeSimple(
 		model,
 		{ systemPrompt: SUMMARIZATION_SYSTEM_PROMPT, messages: summarizationMessages },
 		completionOptions,
@@ -632,9 +629,8 @@ export { serializeConversation } from "./utils.ts";
 /** Generate compaction summary data from prepared session history. */
 export async function compact(
 	preparation: CompactionPreparation,
+	models: Models,
 	model: Model<any>,
-	apiKey: string,
-	headers?: Record<string, string>,
 	customInstructions?: string,
 	signal?: AbortSignal,
 	thinkingLevel?: ThinkingLevel,
@@ -657,40 +653,36 @@ export async function compact(
 	let summary: string;
 
 	if (isSplitTurn && turnPrefixMessages.length > 0) {
-		const [historyResult, turnPrefixResult] = await Promise.all([
+		const historyResult =
 			messagesToSummarize.length > 0
-				? generateSummary(
+				? await generateSummary(
 						messagesToSummarize,
+						models,
 						model,
 						settings.reserveTokens,
-						apiKey,
-						headers,
 						signal,
 						customInstructions,
 						previousSummary,
 						thinkingLevel,
 					)
-				: Promise.resolve(ok<string, CompactionError>("No prior history.")),
-			generateTurnPrefixSummary(
-				turnPrefixMessages,
-				model,
-				settings.reserveTokens,
-				apiKey,
-				headers,
-				signal,
-				thinkingLevel,
-			),
-		]);
+				: ok<string, CompactionError>("No prior history.");
 		if (!historyResult.ok) return err(historyResult.error);
+		const turnPrefixResult = await generateTurnPrefixSummary(
+			turnPrefixMessages,
+			models,
+			model,
+			settings.reserveTokens,
+			signal,
+			thinkingLevel,
+		);
 		if (!turnPrefixResult.ok) return err(turnPrefixResult.error);
 		summary = `${historyResult.value}\n\n---\n\n**Turn Context (split turn):**\n\n${turnPrefixResult.value}`;
 	} else {
 		const summaryResult = await generateSummary(
 			messagesToSummarize,
+			models,
 			model,
 			settings.reserveTokens,
-			apiKey,
-			headers,
 			signal,
 			customInstructions,
 			previousSummary,
@@ -712,10 +704,9 @@ export async function compact(
 }
 async function generateTurnPrefixSummary(
 	messages: AgentMessage[],
+	models: Models,
 	model: Model<any>,
 	reserveTokens: number,
-	apiKey: string,
-	headers?: Record<string, string>,
 	signal?: AbortSignal,
 	thinkingLevel?: ThinkingLevel,
 ): Promise<Result<string, CompactionError>> {
@@ -734,12 +725,12 @@ async function generateTurnPrefixSummary(
 		},
 	];
 
-	const response = await completeSimple(
+	const response = await models.completeSimple(
 		model,
 		{ systemPrompt: SUMMARIZATION_SYSTEM_PROMPT, messages: summarizationMessages },
 		model.reasoning && thinkingLevel && thinkingLevel !== "off"
-			? { maxTokens, signal, apiKey, headers, reasoning: thinkingLevel }
-			: { maxTokens, signal, apiKey, headers },
+			? { maxTokens, signal, reasoning: thinkingLevel }
+			: { maxTokens, signal },
 	);
 	if (response.stopReason === "aborted") {
 		return err(new CompactionError("aborted", response.errorMessage || "Turn prefix summarization aborted"));

packages/agent/src/harness/compaction/utils.ts

@@ -1,4 +1,4 @@
-import type { Message } from "@earendil-works/pi-ai/base";
+import type { Message } from "@earendil-works/pi-ai";
 import type { AgentMessage } from "../../types.ts";
 
 /** File paths touched by a session branch or compaction range. */

packages/agent/src/harness/env/nodejs.ts

@@ -28,6 +28,22 @@ import {
 	toError,
 } from "../types.ts";
 
+const MAX_TIMEOUT_MS = 2_147_483_647;
+const MAX_TIMEOUT_SECONDS = MAX_TIMEOUT_MS / 1000;
+
+function resolveTimeoutMs(timeout: number | undefined): Result<number | undefined, ExecutionError> {
+	if (timeout === undefined) return ok(undefined);
+	if (!Number.isFinite(timeout) || timeout <= 0) {
+		return err(new ExecutionError("timeout", "Invalid timeout: must be a finite number of seconds"));
+	}
+
+	const timeoutMs = timeout * 1000;
+	if (timeoutMs > MAX_TIMEOUT_MS) {
+		return err(new ExecutionError("timeout", `Invalid timeout: maximum is ${MAX_TIMEOUT_SECONDS} seconds`));
+	}
+	return ok(timeoutMs);
+}
+
 function resolvePath(cwd: string, path: string): string {
 	return isAbsolute(path) ? path : resolve(cwd, path);
 }
@@ -258,6 +274,9 @@ export class NodeExecutionEnv implements ExecutionEnv {
 		},
 	): Promise<Result<{ stdout: string; stderr: string; exitCode: number }, ExecutionError>> {
 		if (options?.abortSignal?.aborted) return err(new ExecutionError("aborted", "aborted"));
+		const timeoutMsResult = resolveTimeoutMs(options?.timeout);
+		if (!timeoutMsResult.ok) return err(timeoutMsResult.error);
+		const timeoutMs = timeoutMsResult.value;
 
 		const cwd = options?.cwd ? resolvePath(this.cwd, options.cwd) : this.cwd;
 		const shellConfig = await getShellConfig(this.shellPath);
@@ -310,13 +329,13 @@ export class NodeExecutionEnv implements ExecutionEnv {
 			}
 
 			timeoutId =
-				typeof options?.timeout === "number"
+				timeoutMs !== undefined
 					? setTimeout(() => {
 							timedOut = true;
 							if (child?.pid) {
 								killProcessTree(child.pid);
 							}
-						}, options.timeout * 1000)
+						}, timeoutMs)
 					: undefined;
 
 			if (options?.abortSignal) {

packages/agent/src/harness/messages.ts

@@ -1,4 +1,4 @@
-import type { ImageContent, Message, TextContent } from "@earendil-works/pi-ai/base";
+import type { ImageContent, Message, TextContent } from "@earendil-works/pi-ai";
 import type { AgentMessage } from "../types.ts";
 
 export const COMPACTION_SUMMARY_PREFIX = `The conversation history before this point was compacted into the following summary:

packages/agent/src/harness/session/jsonl-repo.ts

@@ -85,6 +85,7 @@ export class JsonlSessionRepo implements JsonlSessionRepoApi {
 			cwd: options.cwd,
 			sessionId: id,
 			parentSessionPath: options.parentSessionPath,
+			metadata: options.metadata,
 		});
 		return toSession(storage);
 	}
@@ -150,6 +151,7 @@ export class JsonlSessionRepo implements JsonlSessionRepoApi {
 				cwd: options.cwd,
 				sessionId: id,
 				parentSessionPath: options.parentSessionPath ?? sourceMetadata.path,
+				metadata: options.metadata ?? sourceMetadata.metadata,
 			},
 		);
 		for (const entry of forkedEntries) {

packages/agent/src/harness/session/jsonl-storage.ts

@@ -12,6 +12,7 @@ interface SessionHeader {
 	timestamp: string;
 	cwd: string;
 	parentSession?: string;
+	metadata?: Record<string, unknown>;
 }
 
 function updateLabelCache(labelsById: Map<string, string>, entry: SessionTreeEntry): void {
@@ -34,16 +35,14 @@ function buildLabelsById(entries: SessionTreeEntry[]): Map<string, string> {
 
 function generateEntryId(byId: { has(id: string): boolean }): string {
 	for (let i = 0; i < 100; i++) {
-		const id = uuidv7().slice(0, 8);
+		// The uuidv7 prefix is timestamp-derived and nearly constant between calls,
+		// so short ids must come from the random tail.
+		const id = uuidv7().slice(-8);
 		if (!byId.has(id)) return id;
 	}
 	return uuidv7();
 }
 
-function isRecord(value: unknown): value is Record<string, unknown> {
-	return typeof value === "object" && value !== null;
-}
-
 function invalidSession(filePath: string, message: string, cause?: Error): SessionError {
 	return new SessionError("invalid_session", `Invalid JSONL session file ${filePath}: ${message}`, cause);
 }
@@ -63,24 +62,34 @@ function parseHeaderLine(line: string, filePath: string): SessionHeader {
 	} catch (error) {
 		throw invalidSession(filePath, "first line is not a valid session header", toError(error));
 	}
-	if (!isRecord(parsed)) throw invalidSession(filePath, "first line is not a valid session header");
-	if (parsed.type !== "session") throw invalidSession(filePath, "first line is not a valid session header");
-	if (parsed.version !== 3) throw invalidSession(filePath, "unsupported session version");
-	if (typeof parsed.id !== "string" || !parsed.id) throw invalidSession(filePath, "session header is missing id");
-	if (typeof parsed.timestamp !== "string" || !parsed.timestamp) {
+	if (typeof parsed !== "object" || parsed === null) {
+		throw invalidSession(filePath, "first line is not a valid session header");
+	}
+	const header = parsed as Partial<SessionHeader>;
+	if (header.type !== "session") throw invalidSession(filePath, "first line is not a valid session header");
+	if (header.version !== 3) throw invalidSession(filePath, "unsupported session version");
+	if (typeof header.id !== "string" || !header.id) throw invalidSession(filePath, "session header is missing id");
+	if (typeof header.timestamp !== "string" || !header.timestamp) {
 		throw invalidSession(filePath, "session header is missing timestamp");
 	}
-	if (typeof parsed.cwd !== "string" || !parsed.cwd) throw invalidSession(filePath, "session header is missing cwd");
-	if (parsed.parentSession !== undefined && typeof parsed.parentSession !== "string") {
+	if (typeof header.cwd !== "string" || !header.cwd) throw invalidSession(filePath, "session header is missing cwd");
+	if (header.parentSession !== undefined && typeof header.parentSession !== "string") {
 		throw invalidSession(filePath, "session header parentSession must be a string");
 	}
+	if (
+		header.metadata !== undefined &&
+		(typeof header.metadata !== "object" || header.metadata === null || Array.isArray(header.metadata))
+	) {
+		throw invalidSession(filePath, "session header metadata must be an object");
+	}
 	return {
 		type: "session",
 		version: 3,
-		id: parsed.id,
-		timestamp: parsed.timestamp,
-		cwd: parsed.cwd,
-		parentSession: parsed.parentSession,
+		id: header.id,
+		timestamp: header.timestamp,
+		cwd: header.cwd,
+		parentSession: header.parentSession,
+		metadata: header.metadata,
 	};
 }
 
@@ -91,19 +100,28 @@ function parseEntryLine(line: string, filePath: string, lineNumber: number): Ses
 	} catch (error) {
 		throw invalidEntry(filePath, lineNumber, "is not valid JSON", toError(error));
 	}
-	if (!isRecord(parsed)) throw invalidEntry(filePath, lineNumber, "is not a valid session entry");
-	if (typeof parsed.type !== "string") throw invalidEntry(filePath, lineNumber, "is missing entry type");
-	if (typeof parsed.id !== "string" || !parsed.id) throw invalidEntry(filePath, lineNumber, "is missing entry id");
-	if (parsed.parentId !== null && typeof parsed.parentId !== "string") {
+	if (typeof parsed !== "object" || parsed === null) {
+		throw invalidEntry(filePath, lineNumber, "is not a valid session entry");
+	}
+	const entry = parsed as {
+		type?: unknown;
+		id?: unknown;
+		parentId?: unknown;
+		timestamp?: unknown;
+		targetId?: unknown;
+	};
+	if (typeof entry.type !== "string") throw invalidEntry(filePath, lineNumber, "is missing entry type");
+	if (typeof entry.id !== "string" || !entry.id) throw invalidEntry(filePath, lineNumber, "is missing entry id");
+	if (entry.parentId !== null && typeof entry.parentId !== "string") {
 		throw invalidEntry(filePath, lineNumber, "has invalid parentId");
 	}
-	if (typeof parsed.timestamp !== "string" || !parsed.timestamp) {
+	if (typeof entry.timestamp !== "string" || !entry.timestamp) {
 		throw invalidEntry(filePath, lineNumber, "is missing timestamp");
 	}
-	if (parsed.type === "leaf" && parsed.targetId !== null && typeof parsed.targetId !== "string") {
+	if (entry.type === "leaf" && entry.targetId !== null && typeof entry.targetId !== "string") {
 		throw invalidEntry(filePath, lineNumber, "has invalid targetId");
 	}
-	return parsed as unknown as SessionTreeEntry;
+	return entry as SessionTreeEntry;
 }
 
 function leafIdAfterEntry(entry: SessionTreeEntry): string | null {
@@ -117,6 +135,7 @@ function headerToSessionMetadata(header: SessionHeader, path: string): JsonlSess
 		cwd: header.cwd,
 		path,
 		parentSessionPath: header.parentSession,
+		metadata: header.metadata,
 	};
 }
 
@@ -195,6 +214,7 @@ export class JsonlSessionStorage implements SessionStorage<JsonlSessionMetadata>
 			cwd: string;
 			sessionId: string;
 			parentSessionPath?: string;
+			metadata?: Record<string, unknown>;
 		},
 	): Promise<JsonlSessionStorage> {
 		const header: SessionHeader = {
@@ -204,6 +224,7 @@ export class JsonlSessionStorage implements SessionStorage<JsonlSessionMetadata>
 			timestamp: new Date().toISOString(),
 			cwd: options.cwd,
 			parentSession: options.parentSessionPath,
+			metadata: options.metadata,
 		};
 		getFileSystemResultOrThrow(
 			await fs.writeFile(filePath, `${JSON.stringify(header)}\n`),

packages/agent/src/harness/session/memory-storage.ts

@@ -27,7 +27,9 @@ function buildLabelsById(entries: SessionTreeEntry[]): Map<string, string> {
 
 function generateEntryId(byId: { has(id: string): boolean }): string {
 	for (let i = 0; i < 100; i++) {
-		const id = uuidv7().slice(0, 8);
+		// The uuidv7 prefix is timestamp-derived and nearly constant between calls,
+		// so short ids must come from the random tail.
+		const id = uuidv7().slice(-8);
 		if (!byId.has(id)) return id;
 	}
 	return uuidv7();

packages/agent/src/harness/session/session.ts

@@ -1,4 +1,4 @@
-import type { ImageContent, TextContent } from "@earendil-works/pi-ai/base";
+import type { ImageContent, TextContent } from "@earendil-works/pi-ai";
 import type { AgentMessage } from "../../types.ts";
 import { createBranchSummaryMessage, createCompactionSummaryMessage, createCustomMessage } from "../messages.ts";
 import type {
@@ -19,11 +19,25 @@ import type {
 } from "../types.ts";
 import { SessionError } from "../types.ts";
 
-export function buildSessionContext(pathEntries: SessionTreeEntry[]): SessionContext {
+export type ContextEntryTransform = (entries: readonly SessionTreeEntry[]) => readonly SessionTreeEntry[];
+
+export type CustomEntryContextMessageProjector = (
+	entry: CustomEntry,
+	index: number,
+	entries: readonly SessionTreeEntry[],
+) => readonly AgentMessage[] | undefined;
+
+export interface SessionContextBuildOptions {
+	/** Additional entry transforms applied after the default compaction transform. */
+	entryTransforms?: readonly ContextEntryTransform[];
+	/** Optional custom-entry projectors. Custom entries are omitted from model context by default. */
+	entryProjectors?: Readonly<Record<string, CustomEntryContextMessageProjector>>;
+}
+
+function deriveSessionContextState(pathEntries: readonly SessionTreeEntry[]): Omit<SessionContext, "messages"> {
 	let thinkingLevel = "off";
 	let model: { provider: string; modelId: string } | null = null;
 	let activeToolNames: string[] | null = null;
-	let compaction: CompactionEntry | null = null;
 
 	for (const entry of pathEntries) {
 		if (entry.type === "thinking_level_change") {
@@ -34,56 +48,99 @@ export function buildSessionContext(pathEntries: SessionTreeEntry[]): SessionCon
 			model = { provider: entry.message.provider, modelId: entry.message.model };
 		} else if (entry.type === "active_tools_change") {
 			activeToolNames = [...entry.activeToolNames];
-		} else if (entry.type === "compaction") {
+		}
+	}
+
+	return { thinkingLevel, model, activeToolNames };
+}
+
+export function defaultContextEntryTransform(pathEntries: readonly SessionTreeEntry[]): SessionTreeEntry[] {
+	let compaction: CompactionEntry | null = null;
+	for (const entry of pathEntries) {
+		if (entry.type === "compaction") {
 			compaction = entry;
 		}
 	}
-
-	const messages: AgentMessage[] = [];
-	const appendMessage = (entry: SessionTreeEntry) => {
-		if (entry.type === "message") {
-			messages.push(entry.message as AgentMessage);
-		} else if (entry.type === "custom_message") {
-			messages.push(
-				createCustomMessage(
-					entry.customType,
-					entry.content as string | (TextContent | ImageContent)[],
-					entry.display,
-					entry.details,
-					entry.timestamp,
-				),
-			);
-		} else if (entry.type === "branch_summary" && entry.summary) {
-			messages.push(createBranchSummaryMessage(entry.summary, entry.fromId, entry.timestamp));
-		}
-	};
-
-	if (compaction) {
-		messages.push(createCompactionSummaryMessage(compaction.summary, compaction.tokensBefore, compaction.timestamp));
-		const compactionIdx = pathEntries.findIndex((e) => e.type === "compaction" && e.id === compaction.id);
-		let foundFirstKept = false;
-		for (let i = 0; i < compactionIdx; i++) {
-			const entry = pathEntries[i]!;
-			if (entry.id === compaction.firstKeptEntryId) foundFirstKept = true;
-			if (foundFirstKept) appendMessage(entry);
-		}
-		for (let i = compactionIdx + 1; i < pathEntries.length; i++) {
-			appendMessage(pathEntries[i]!);
-		}
-	} else {
-		for (const entry of pathEntries) {
-			appendMessage(entry);
-		}
+	if (!compaction) {
+		return [...pathEntries];
 	}
 
-	return { messages, thinkingLevel, model, activeToolNames };
+	const entries: SessionTreeEntry[] = [compaction];
+	const compactionIdx = pathEntries.findIndex((entry) => entry.type === "compaction" && entry.id === compaction.id);
+	let foundFirstKept = false;
+	for (let i = 0; i < compactionIdx; i++) {
+		const entry = pathEntries[i]!;
+		if (entry.id === compaction.firstKeptEntryId) foundFirstKept = true;
+		if (foundFirstKept) entries.push(entry);
+	}
+	for (let i = compactionIdx + 1; i < pathEntries.length; i++) {
+		entries.push(pathEntries[i]!);
+	}
+	return entries;
+}
+
+export function buildContextEntries(
+	pathEntries: readonly SessionTreeEntry[],
+	options: SessionContextBuildOptions = {},
+): SessionTreeEntry[] {
+	let entries = defaultContextEntryTransform(pathEntries);
+	for (const transform of options.entryTransforms ?? []) {
+		entries = [...transform(entries)];
+	}
+	return entries;
+}
+
+export function sessionEntryToContextMessages(
+	entry: SessionTreeEntry,
+	index: number,
+	entries: readonly SessionTreeEntry[],
+	options: SessionContextBuildOptions = {},
+): AgentMessage[] {
+	if (entry.type === "message") {
+		return [entry.message as AgentMessage];
+	}
+	if (entry.type === "custom_message") {
+		return [
+			createCustomMessage(
+				entry.customType,
+				entry.content as string | (TextContent | ImageContent)[],
+				entry.display,
+				entry.details,
+				entry.timestamp,
+			),
+		];
+	}
+	if (entry.type === "compaction") {
+		return [createCompactionSummaryMessage(entry.summary, entry.tokensBefore, entry.timestamp)];
+	}
+	if (entry.type === "branch_summary" && entry.summary) {
+		return [createBranchSummaryMessage(entry.summary, entry.fromId, entry.timestamp)];
+	}
+	if (entry.type === "custom") {
+		return [...(options.entryProjectors?.[entry.customType]?.(entry, index, entries) ?? [])];
+	}
+	return [];
+}
+
+export function buildSessionContext(
+	pathEntries: readonly SessionTreeEntry[],
+	options: SessionContextBuildOptions = {},
+): SessionContext {
+	const state = deriveSessionContextState(pathEntries);
+	const contextEntries = buildContextEntries(pathEntries, options);
+	const messages = contextEntries.flatMap((entry, index) =>
+		sessionEntryToContextMessages(entry, index, contextEntries, options),
+	);
+	return { ...state, messages };
 }
 
 export class Session<TMetadata extends SessionMetadata = SessionMetadata> {
 	private storage: SessionStorage<TMetadata>;
+	private contextBuildOptions: SessionContextBuildOptions;
 
-	constructor(storage: SessionStorage<TMetadata>) {
+	constructor(storage: SessionStorage<TMetadata>, contextBuildOptions: SessionContextBuildOptions = {}) {
 		this.storage = storage;
+		this.contextBuildOptions = contextBuildOptions;
 	}
 
 	getMetadata(): Promise<TMetadata> {
@@ -111,8 +168,22 @@ export class Session<TMetadata extends SessionMetadata = SessionMetadata> {
 		return this.storage.getPathToRoot(leafId);
 	}
 
-	async buildContext(): Promise<SessionContext> {
-		return buildSessionContext(await this.getBranch());
+	async buildContextEntries(options: SessionContextBuildOptions = {}): Promise<SessionTreeEntry[]> {
+		return buildContextEntries(await this.getBranch(), this.mergeContextBuildOptions(options));
+	}
+
+	async buildContext(options: SessionContextBuildOptions = {}): Promise<SessionContext> {
+		return buildSessionContext(await this.getBranch(), this.mergeContextBuildOptions(options));
+	}
+
+	private mergeContextBuildOptions(options: SessionContextBuildOptions): SessionContextBuildOptions {
+		return {
+			entryTransforms: [...(this.contextBuildOptions.entryTransforms ?? []), ...(options.entryTransforms ?? [])],
+			entryProjectors: {
+				...(this.contextBuildOptions.entryProjectors ?? {}),
+				...(options.entryProjectors ?? {}),
+			},
+		};
 	}
 
 	getLabel(id: string): Promise<string | undefined> {
@@ -234,12 +305,13 @@ export class Session<TMetadata extends SessionMetadata = SessionMetadata> {
 	}
 
 	async appendSessionName(name: string): Promise<string> {
+		const sanitizedName = name.replace(/[\r\n]+/g, " ").trim();
 		return this.appendTypedEntry({
 			type: "session_info",
 			id: await this.storage.createEntryId(),
 			parentId: await this.storage.getLeafId(),
 			timestamp: new Date().toISOString(),
-			name: name.trim(),
+			name: sanitizedName,
 		} satisfies SessionInfoEntry);
 	}
 

packages/agent/src/harness/types.ts

@@ -1,5 +1,5 @@
-import type { ImageContent, Model, SimpleStreamOptions, TextContent, Transport } from "@earendil-works/pi-ai/base";
-import type { AgentEvent, AgentMessage, AgentTool, QueueMode, ThinkingLevel } from "../types.ts";
+import type { ImageContent, Model, Models, SimpleStreamOptions, TextContent, Transport } from "@earendil-works/pi-ai";
+import type { AgentEvent, AgentMessage, AgentTool, QueueMode, ThinkingLevel } from "../index.ts";
 import type { Session } from "./session/session.ts";
 
 /** Result of a fallible operation. Expected failures are returned as `ok: false` instead of thrown. */
@@ -240,22 +240,6 @@ export interface FileInfo {
 	mtimeMs: number;
 }
 
-/** Options for {@link Shell.exec}. */
-export interface ExecutionEnvExecOptions {
-	/** Working directory for the command. Relative paths are resolved against {@link ExecutionEnv.cwd}. Defaults to {@link ExecutionEnv.cwd}. */
-	cwd?: string;
-	/** Additional environment variables for the command. Values override the environment defaults. Defaults to no overrides. */
-	env?: Record<string, string>;
-	/** Timeout in seconds. Implementations should return a timeout error when the command exceeds this duration. Defaults to no timeout. */
-	timeout?: number;
-	/** Abort signal used to terminate the command. Defaults to no abort signal. */
-	abortSignal?: AbortSignal;
-	/** Called with stdout chunks as they are produced. */
-	onStdout?: (chunk: string) => void;
-	/** Called with stderr chunks as they are produced. */
-	onStderr?: (chunk: string) => void;
-}
-
 /**
  * Filesystem capability used by the harness.
  *
@@ -317,12 +301,28 @@ export interface FileSystem {
 	cleanup(): Promise<void>;
 }
 
+/** Options for {@link Shell.exec}. */
+export interface ShellExecOptions {
+	/** Working directory for the command. Relative paths are resolved against {@link ExecutionEnv.cwd}. Defaults to {@link ExecutionEnv.cwd}. */
+	cwd?: string;
+	/** Additional environment variables for the command. Values override the environment defaults. Defaults to no overrides. */
+	env?: Record<string, string>;
+	/** Timeout in seconds. Implementations should return a timeout error when the command exceeds this duration. Defaults to no timeout. */
+	timeout?: number;
+	/** Abort signal used to terminate the command. Defaults to no abort signal. */
+	abortSignal?: AbortSignal;
+	/** Called with stdout chunks as they are produced. */
+	onStdout?: (chunk: string) => void;
+	/** Called with stderr chunks as they are produced. */
+	onStderr?: (chunk: string) => void;
+}
+
 /** Shell execution capability used by the harness. */
 export interface Shell {
 	/** Execute a shell command in {@link FileSystem.cwd} unless `options.cwd` is provided. */
 	exec(
 		command: string,
-		options?: ExecutionEnvExecOptions,
+		options?: ShellExecOptions,
 	): Promise<Result<{ stdout: string; stderr: string; exitCode: number }, ExecutionError>>;
 	/** Release shell resources. Must be best-effort and must not throw or reject. */
 	cleanup(): Promise<void>;
@@ -435,6 +435,7 @@ export interface JsonlSessionMetadata extends SessionMetadata {
 	cwd: string;
 	path: string;
 	parentSessionPath?: string;
+	metadata?: Record<string, unknown>;
 }
 
 export interface SessionStorage<TMetadata extends SessionMetadata = SessionMetadata> {
@@ -480,6 +481,7 @@ export interface SessionRepo<
 export interface JsonlSessionCreateOptions extends SessionCreateOptions {
 	cwd: string;
 	parentSessionPath?: string;
+	metadata?: Record<string, unknown>;
 }
 
 export interface JsonlSessionListOptions {
@@ -802,6 +804,12 @@ export interface AgentHarnessOptions<
 > {
 	env: ExecutionEnv;
 	session: Session;
+	/**
+	 * Provider collection used for all model requests (turn streaming,
+	 * compaction, branch summarization). Auth resolves through the providers'
+	 * auth.
+	 */
+	models: Models;
 	tools?: TTool[];
 	/**
 	 * Concrete resources available to explicit invocation methods and system-prompt callbacks.
@@ -818,9 +826,6 @@ export interface AgentHarnessOptions<
 				activeTools: TTool[];
 				resources: AgentHarnessResources<TSkill, TPromptTemplate>;
 		  }) => string | Promise<string>);
-	getApiKeyAndHeaders?: (
-		model: Model<any>,
-	) => Promise<{ apiKey: string; headers?: Record<string, string> } | undefined>;
 	/** Curated stream/provider request options. Snapshotted at turn start. */
 	streamOptions?: AgentHarnessStreamOptions;
 	model: Model<any>;

packages/agent/src/harness/utils/shell-output.ts

@@ -1,15 +1,7 @@
-import {
-	type ExecutionEnv,
-	type ExecutionEnvExecOptions,
-	ExecutionError,
-	err,
-	ok,
-	type Result,
-	toError,
-} from "../types.ts";
+import { type ExecutionEnv, ExecutionError, err, ok, type Result, type ShellExecOptions, toError } from "../types.ts";
 import { DEFAULT_MAX_BYTES, truncateTail } from "./truncate.ts";
 
-export interface ShellCaptureOptions extends Omit<ExecutionEnvExecOptions, "onStdout" | "onStderr"> {
+export interface ShellCaptureOptions extends Omit<ShellExecOptions, "onStdout" | "onStderr"> {
 	onChunk?: (chunk: string) => void;
 }
 

packages/agent/src/index.ts

@@ -1,5 +1,46 @@
-// Import the default pi-ai entrypoint so that all built-in providers register
-// automatically. Unlike "@earendil-works/pi-ai/base" which does not.
-import "@earendil-works/pi-ai";
-
-export * from "./base.ts";
+// Core Agent
+export * from "./agent.ts";
+// Loop functions
+export * from "./agent-loop.ts";
+export * from "./harness/agent-harness.ts";
+export {
+	type BranchPreparation,
+	type BranchSummaryDetails,
+	type CollectEntriesResult,
+	collectEntriesForBranchSummary,
+	generateBranchSummary,
+	prepareBranchEntries,
+} from "./harness/compaction/branch-summarization.ts";
+export {
+	calculateContextTokens,
+	compact,
+	DEFAULT_COMPACTION_SETTINGS,
+	estimateContextTokens,
+	estimateTokens,
+	findCutPoint,
+	findTurnStartIndex,
+	generateSummary,
+	getLastAssistantUsage,
+	prepareCompaction,
+	serializeConversation,
+	shouldCompact,
+} from "./harness/compaction/compaction.ts";
+export * from "./harness/messages.ts";
+export * from "./harness/prompt-templates.ts";
+export * from "./harness/session/jsonl-repo.ts";
+export * from "./harness/session/jsonl-storage.ts";
+export * from "./harness/session/memory-repo.ts";
+export * from "./harness/session/memory-storage.ts";
+export * from "./harness/session/repo-utils.ts";
+export * from "./harness/session/session.ts";
+export { uuidv7 } from "./harness/session/uuid.ts";
+export * from "./harness/skills.ts";
+export * from "./harness/system-prompt.ts";
+// Harness
+export * from "./harness/types.ts";
+export * from "./harness/utils/shell-output.ts";
+export * from "./harness/utils/truncate.ts";
+// Proxy utilities
+export * from "./proxy.ts";
+// Types
+export * from "./types.ts";

packages/agent/src/proxy.ts

@@ -14,7 +14,7 @@ import {
 	type SimpleStreamOptions,
 	type StopReason,
 	type ToolCall,
-} from "@earendil-works/pi-ai/base";
+} from "@earendil-works/pi-ai";
 
 // Create stream class matching ProxyMessageEventStream
 class ProxyMessageEventStream extends EventStream<AssistantMessageEvent, AssistantMessage> {

packages/agent/src/types.ts

@@ -1,19 +1,22 @@
 import type {
+	Api,
 	AssistantMessage,
 	AssistantMessageEvent,
+	AssistantMessageEventStream,
+	Context,
 	ImageContent,
 	Message,
 	Model,
 	SimpleStreamOptions,
-	streamSimple,
 	TextContent,
 	Tool,
 	ToolResultMessage,
-} from "@earendil-works/pi-ai/base";
+} from "@earendil-works/pi-ai";
 import type { Static, TSchema } from "typebox";
 
 /**
- * Stream function used by the agent loop.
+ * Stream function used by the agent loop. `Models.streamSimple` satisfies
+ * this shape.
  *
  * Contract:
  * - Must not throw or return a rejected promise for request/model/runtime failures.
@@ -22,8 +25,10 @@ import type { Static, TSchema } from "typebox";
  *   final AssistantMessage with stopReason "error" or "aborted" and errorMessage.
  */
 export type StreamFn = (
-	...args: Parameters<typeof streamSimple>
-) => ReturnType<typeof streamSimple> | Promise<ReturnType<typeof streamSimple>>;
+	model: Model<Api>,
+	context: Context,
+	options?: SimpleStreamOptions,
+) => AssistantMessageEventStream | Promise<AssistantMessageEventStream>;
 
 /**
  * Configuration for how tool calls from a single assistant message are executed.

packages/agent/test/agent-loop.test.ts

@@ -307,6 +307,79 @@ describe("agentLoop with AgentMessage", () => {
 		}
 	});
 
+	it("should not execute tool calls from a length-truncated assistant message", async () => {
+		const toolSchema = Type.Object({ value: Type.String() });
+		const executed: string[] = [];
+		const tool: AgentTool<typeof toolSchema, { value: string }> = {
+			name: "echo",
+			label: "Echo",
+			description: "Echo tool",
+			parameters: toolSchema,
+			async execute(_toolCallId, params) {
+				executed.push(params.value);
+				return {
+					content: [{ type: "text", text: `echoed: ${params.value}` }],
+					details: { value: params.value },
+				};
+			},
+		};
+
+		const context: AgentContext = {
+			systemPrompt: "",
+			messages: [],
+			tools: [tool],
+		};
+
+		const config: AgentLoopConfig = {
+			model: createModel(),
+			convertToLlm: identityConverter,
+		};
+
+		let callIndex = 0;
+		const streamFn = () => {
+			const stream = new MockAssistantStream();
+			queueMicrotask(() => {
+				if (callIndex === 0) {
+					// Output hit the token limit mid tool call. The salvage parser can
+					// produce arguments that validate but are silently truncated, so
+					// nothing in this message may execute.
+					const message = createAssistantMessage(
+						[{ type: "toolCall", id: "tool-1", name: "echo", arguments: { value: "hel" } }],
+						"length",
+					);
+					stream.push({ type: "done", reason: "length", message });
+				} else {
+					const message = createAssistantMessage([{ type: "text", text: "done" }]);
+					stream.push({ type: "done", reason: "stop", message });
+				}
+				callIndex++;
+			});
+			return stream;
+		};
+
+		const events: AgentEvent[] = [];
+		const stream = agentLoop([createUserMessage("echo something")], context, config, undefined, streamFn);
+		for await (const event of stream) {
+			events.push(event);
+		}
+
+		// The tool must never execute with potentially truncated arguments.
+		expect(executed).toEqual([]);
+
+		const toolEnd = events.find((e) => e.type === "tool_execution_end");
+		expect(toolEnd).toBeDefined();
+		if (toolEnd?.type === "tool_execution_end") {
+			expect(toolEnd.isError).toBe(true);
+			const text = toolEnd.result.content.find((c: { type: string }) => c.type === "text");
+			expect(text && "text" in text ? text.text : "").toContain("output token limit");
+		}
+
+		// The loop continues so the model can re-issue the tool call.
+		expect(callIndex).toBe(2);
+		const messages = await stream.result();
+		expect(messages[messages.length - 1].role).toBe("assistant");
+	});
+
 	it("should execute mutated beforeToolCall args without revalidation", async () => {
 		const toolSchema = Type.Object({ value: Type.String() });
 		const executed: Array<string | number> = [];

packages/agent/test/agent.test.ts

@@ -1,4 +1,4 @@
-import { type AssistantMessage, type AssistantMessageEvent, EventStream, getModel } from "@earendil-works/pi-ai";
+import { type AssistantMessage, type AssistantMessageEvent, EventStream, getModel } from "@earendil-works/pi-ai/compat";
 import { Type } from "typebox";
 import { describe, expect, it } from "vitest";
 import { Agent, type AgentEvent, type AgentTool, type AgentToolUpdateCallback } from "../src/index.ts";
@@ -630,6 +630,47 @@ describe("Agent", () => {
 		expect(responseCount).toBe(2);
 	});
 
+	it("keeps legacy prepareNextTurn signal callback behavior", async () => {
+		const schema = Type.Object({});
+		const tool: AgentTool<typeof schema> = {
+			name: "noop",
+			label: "Noop",
+			description: "Noop tool",
+			parameters: schema,
+			execute: async () => ({ content: [{ type: "text", text: "ok" }], details: {} }),
+		};
+		let requestCount = 0;
+		let sawAbortSignal = false;
+		const agent = new Agent({
+			initialState: { tools: [tool] },
+			prepareNextTurn: async (signal) => {
+				sawAbortSignal = signal instanceof AbortSignal;
+				return undefined;
+			},
+			streamFn: () => {
+				requestCount++;
+				const stream = new MockAssistantStream();
+				queueMicrotask(() => {
+					if (requestCount === 1) {
+						const message = createAssistantToolUseMessage([
+							{ type: "toolCall", id: "tool-1", name: "noop", arguments: {} },
+						]);
+						stream.push({ type: "done", reason: "toolUse", message });
+						return;
+					}
+					const message = createAssistantMessage("done");
+					stream.push({ type: "done", reason: "stop", message });
+				});
+				return stream;
+			},
+		});
+
+		await agent.prompt("start");
+
+		expect(requestCount).toBe(2);
+		expect(sawAbortSignal).toBe(true);
+	});
+
 	it("forwards sessionId to streamFn options", async () => {
 		let receivedSessionId: string | undefined;
 		const agent = new Agent({

packages/agent/test/e2e.test.ts

@@ -9,7 +9,7 @@ import {
 	registerFauxProvider,
 	type ToolResultMessage,
 	type UserMessage,
-} from "@earendil-works/pi-ai";
+} from "@earendil-works/pi-ai/compat";
 import { afterEach, describe, expect, it } from "vitest";
 import { Agent, type AgentEvent } from "../src/index.ts";
 import { calculateTool } from "./utils/calculate.ts";

packages/agent/test/harness/agent-harness-stream.test.ts

@@ -1,18 +1,27 @@
-import { fauxAssistantMessage, fauxToolCall, registerFauxProvider, type StreamOptions } from "@earendil-works/pi-ai";
-import { afterEach, describe, expect, it } from "vitest";
+import {
+	createModels,
+	type FauxProviderHandle,
+	fauxAssistantMessage,
+	fauxProvider,
+	fauxToolCall,
+	type StreamOptions,
+} from "@earendil-works/pi-ai";
+import { describe, expect, it } from "vitest";
 import { AgentHarness } from "../../src/harness/agent-harness.ts";
 import { NodeExecutionEnv } from "../../src/harness/env/nodejs.ts";
 import { InMemorySessionStorage } from "../../src/harness/session/memory-storage.ts";
 import { Session } from "../../src/harness/session/session.ts";
 import { calculateTool } from "../utils/calculate.ts";
 
-const registrations: Array<{ unregister(): void }> = [];
+/** Shared collection; each faux provider gets a unique id so coexisting fakes route correctly. */
+const models = createModels();
+let fauxCount = 0;
 
-afterEach(() => {
-	for (const registration of registrations.splice(0)) {
-		registration.unregister();
-	}
-});
+function newFaux(): FauxProviderHandle {
+	const faux = fauxProvider({ provider: `faux-${++fauxCount}` });
+	models.setProvider(faux.provider);
+	return faux;
+}
 
 function createHarness(options: ConstructorParameters<typeof AgentHarness>[0]): AgentHarness {
 	return new AgentHarness(options);
@@ -27,10 +36,9 @@ function captureOptions(options: StreamOptions | undefined): StreamOptions {
 }
 
 describe("AgentHarness stream configuration", () => {
-	it("snapshots stream options and merges auth headers before provider request hooks", async () => {
+	it("snapshots stream options before provider request hooks", async () => {
 		let capturedOptions: StreamOptions | undefined;
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([
 			(_context, options) => {
 				capturedOptions = options;
@@ -40,6 +48,7 @@ describe("AgentHarness stream configuration", () => {
 
 		const session = new Session(new InMemorySessionStorage({ metadata: { id: "session-1", createdAt: "now" } }));
 		const harness = createHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session,
 			model: registration.getModel(),
@@ -51,12 +60,11 @@ describe("AgentHarness stream configuration", () => {
 				metadata: { base: true },
 				cacheRetention: "none",
 			},
-			getApiKeyAndHeaders: async () => ({ apiKey: "secret", headers: { "x-auth": "auth" } }),
 		});
 
 		harness.on("before_provider_request", (event) => {
 			expect(event.sessionId).toBe("session-1");
-			expect(event.streamOptions.headers).toEqual({ "x-base": "base", "x-auth": "auth" });
+			expect(event.streamOptions.headers).toEqual({ "x-base": "base" });
 			return {
 				streamOptions: {
 					headers: { "x-hook": "hook" },
@@ -68,21 +76,19 @@ describe("AgentHarness stream configuration", () => {
 		await harness.prompt("hello");
 
 		expect(capturedOptions).toMatchObject({
-			apiKey: "secret",
 			timeoutMs: 1000,
 			maxRetries: 2,
 			maxRetryDelayMs: 3000,
 			sessionId: "session-1",
 			cacheRetention: "none",
 		});
-		expect(capturedOptions?.headers).toEqual({ "x-base": "base", "x-auth": "auth", "x-hook": "hook" });
+		expect(capturedOptions?.headers).toEqual({ "x-base": "base", "x-hook": "hook" });
 		expect(capturedOptions?.metadata).toEqual({ base: true, hook: true });
 	});
 
 	it("chains provider request patches and supports deletion semantics", async () => {
 		let capturedOptions: StreamOptions | undefined;
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([
 			(_context, options) => {
 				capturedOptions = options;
@@ -91,6 +97,7 @@ describe("AgentHarness stream configuration", () => {
 		]);
 
 		const harness = createHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -133,8 +140,7 @@ describe("AgentHarness stream configuration", () => {
 
 	it("uses updated stream options for save-point snapshots without mutating the active request", async () => {
 		const capturedOptions: StreamOptions[] = [];
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([
 			(_context, options) => {
 				capturedOptions.push(captureOptions(options));
@@ -149,6 +155,7 @@ describe("AgentHarness stream configuration", () => {
 		]);
 
 		const harness = createHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -174,8 +181,7 @@ describe("AgentHarness stream configuration", () => {
 	it("chains provider payload hooks", async () => {
 		const seenPayloads: unknown[] = [];
 		let finalPayload: unknown;
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([
 			async (_context, options, _state, model) => {
 				finalPayload = await options?.onPayload?.({ steps: ["provider"] }, model);
@@ -184,6 +190,7 @@ describe("AgentHarness stream configuration", () => {
 		]);
 
 		const harness = createHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),

packages/agent/test/harness/agent-harness.test.ts

@@ -1,5 +1,13 @@
-import { fauxAssistantMessage, fauxToolCall, getModel, registerFauxProvider } from "@earendil-works/pi-ai";
-import { afterEach, describe, expect, it } from "vitest";
+import {
+	createModels,
+	type FauxProviderHandle,
+	fauxAssistantMessage,
+	fauxProvider,
+	fauxToolCall,
+	type RegisterFauxProviderOptions,
+} from "@earendil-works/pi-ai";
+import { getModel } from "@earendil-works/pi-ai/compat";
+import { describe, expect, it } from "vitest";
 import { AgentHarness } from "../../src/harness/agent-harness.ts";
 import { NodeExecutionEnv } from "../../src/harness/env/nodejs.ts";
 import { InMemorySessionStorage } from "../../src/harness/session/memory-storage.ts";
@@ -17,7 +25,15 @@ interface AppPromptTemplate extends PromptTemplate {
 	source: "project" | "user";
 }
 
-const registrations: Array<{ unregister(): void }> = [];
+/** Shared collection; each faux provider gets a unique id so coexisting fakes route correctly. */
+const models = createModels();
+let fauxCount = 0;
+
+function newFaux(options: RegisterFauxProviderOptions = {}): FauxProviderHandle {
+	const faux = fauxProvider({ provider: `faux-${++fauxCount}`, ...options });
+	models.setProvider(faux.provider);
+	return faux;
+}
 
 function textFromUserMessages(messages: Array<{ role: string; content: unknown }>): string[] {
 	return messages.flatMap((message) => {
@@ -44,18 +60,13 @@ function getReasoning(options: unknown): unknown {
 	return options.reasoning;
 }
 
-afterEach(() => {
-	for (const registration of registrations.splice(0)) {
-		registration.unregister();
-	}
-});
-
 describe("AgentHarness", () => {
 	it("constructs directly and exposes queue modes", () => {
 		const session = new Session(new InMemorySessionStorage());
 		const env = new NodeExecutionEnv({ cwd: process.cwd() });
 		const initialModel = getModel("anthropic", "claude-sonnet-4-5");
 		const harness = new AgentHarness({
+			models,
 			env,
 			session,
 			model: initialModel,
@@ -76,8 +87,7 @@ describe("AgentHarness", () => {
 	});
 
 	it("drains one queued steering message at a time and emits queue updates", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		const userCounts: number[] = [];
 		registration.setResponses([
 			(context) => {
@@ -94,6 +104,7 @@ describe("AgentHarness", () => {
 			},
 		]);
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -119,8 +130,7 @@ describe("AgentHarness", () => {
 	});
 
 	it("appends before_agent_start messages and persists them", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		let requestText: string[] = [];
 		registration.setResponses([
 			(context) => {
@@ -130,6 +140,7 @@ describe("AgentHarness", () => {
 		]);
 		const session = new Session(new InMemorySessionStorage());
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session,
 			model: registration.getModel(),
@@ -151,8 +162,7 @@ describe("AgentHarness", () => {
 	});
 
 	it("abort clears steer and follow-up queues but preserves next-turn messages", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		let releaseFirstResponse: (() => void) | undefined;
 		let abortedSignal: AbortSignal | undefined;
 		const firstResponseReleased = new Promise<void>((resolve) => {
@@ -171,6 +181,7 @@ describe("AgentHarness", () => {
 			},
 		]);
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -206,8 +217,7 @@ describe("AgentHarness", () => {
 	});
 
 	it("drains follow-up messages one at a time after the agent would otherwise stop", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		const userCounts: number[] = [];
 		registration.setResponses([
 			(context) => {
@@ -224,6 +234,7 @@ describe("AgentHarness", () => {
 			},
 		]);
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -249,11 +260,11 @@ describe("AgentHarness", () => {
 	});
 
 	it("settles thrown hook failures with persisted assistant error messages", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([() => fauxAssistantMessage("should not be used")]);
 		const session = new Session(new InMemorySessionStorage());
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session,
 			model: registration.getModel(),
@@ -280,13 +291,12 @@ describe("AgentHarness", () => {
 	});
 
 	it("refreshes model, thinking level, resources, system prompt, and active tools at save points", async () => {
-		const registration = registerFauxProvider({
+		const registration = newFaux({
 			models: [
 				{ id: "first", reasoning: true },
 				{ id: "second", reasoning: true },
 			],
 		});
-		registrations.push(registration);
 		const secondModel = registration.getModel("second");
 		if (!secondModel) throw new Error("missing second faux model");
 		const captured: Array<{ modelId: string; reasoning: unknown; systemPrompt: string; tools: string[] }> = [];
@@ -313,6 +323,7 @@ describe("AgentHarness", () => {
 			},
 		]);
 		const harness = new AgentHarness<Skill, PromptTemplate, AgentTool>({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -345,11 +356,11 @@ describe("AgentHarness", () => {
 	});
 
 	it("orders pending listener session writes after agent-emitted messages", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([() => fauxAssistantMessage("ok")]);
 		const session = new Session(new InMemorySessionStorage());
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session,
 			model: registration.getModel(),
@@ -376,11 +387,11 @@ describe("AgentHarness", () => {
 	});
 
 	it("waitForIdle waits for external run settlement and awaited listeners", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([() => fauxAssistantMessage("ok")]);
 		const barrier = deferred();
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session: new Session(new InMemorySessionStorage()),
 			model: registration.getModel(),
@@ -408,8 +419,7 @@ describe("AgentHarness", () => {
 	});
 
 	it("runs tool_call and tool_result hooks through the direct loop", async () => {
-		const registration = registerFauxProvider();
-		registrations.push(registration);
+		const registration = newFaux();
 		registration.setResponses([
 			() =>
 				fauxAssistantMessage(fauxToolCall("calculate", { expression: "2 + 2" }, { id: "call-1" }), {
@@ -418,6 +428,7 @@ describe("AgentHarness", () => {
 		]);
 		const session = new Session(new InMemorySessionStorage());
 		const harness = new AgentHarness({
+			models,
 			env: new NodeExecutionEnv({ cwd: process.cwd() }),
 			session,
 			model: registration.getModel(),
@@ -462,6 +473,7 @@ describe("AgentHarness", () => {
 		const inspectTool: AppTool = { ...calculateTool, name: "inspect", source: "builtin" };
 		const searchTool: AppTool = { ...calculateTool, name: "search", source: "extension" };
 		const harness = new AgentHarness<AppSkill, AppPromptTemplate, AppTool>({
+			models,
 			env,
 			session,
 			model,
@@ -530,11 +542,12 @@ describe("AgentHarness", () => {
 		const env = new NodeExecutionEnv({ cwd: process.cwd() });
 		const model = getModel("anthropic", "claude-sonnet-4-5");
 		expect(
-			() => new AgentHarness({ env, session, model, tools: [calculateTool], activeToolNames: ["missing"] }),
+			() => new AgentHarness({ env, session, models, model, tools: [calculateTool], activeToolNames: ["missing"] }),
 		).toThrow(/Unknown tool/);
 		expect(
 			() =>
 				new AgentHarness({
+					models,
 					env,
 					session,
 					model,
@@ -545,6 +558,7 @@ describe("AgentHarness", () => {
 		expect(
 			() =>
 				new AgentHarness({
+					models,
 					env,
 					session,
 					model,
@@ -558,7 +572,7 @@ describe("AgentHarness", () => {
 		const session = new Session(new InMemorySessionStorage());
 		const env = new NodeExecutionEnv({ cwd: process.cwd() });
 		const model = getModel("anthropic", "claude-sonnet-4-5");
-		const harness = new AgentHarness<AppSkill, AppPromptTemplate, AgentTool>({ env, session, model });
+		const harness = new AgentHarness<AppSkill, AppPromptTemplate, AgentTool>({ env, session, models, model });
 		const skill: AppSkill = {
 			name: "inspect",
 			description: "Inspect things",

packages/agent/test/harness/compaction.test.ts

@@ -1,13 +1,14 @@
 import {
 	type AssistantMessage,
-	type FauxProviderRegistration,
+	createModels,
+	type FauxProviderHandle,
 	fauxAssistantMessage,
+	fauxProvider,
 	type Message,
 	type Model,
-	registerFauxProvider,
 	type Usage,
 } from "@earendil-works/pi-ai";
-import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { beforeEach, describe, expect, it } from "vitest";
 import {
 	type CompactionPreparation,
 	calculateContextTokens,
@@ -121,11 +122,13 @@ function createModelChangeEntry(provider: string, modelId: string, parentId: str
 	};
 }
 
-function createFauxModel(
-	reasoning: boolean,
-	maxTokens = 8192,
-): { faux: FauxProviderRegistration; model: Model<string> } {
-	const faux = registerFauxProvider({
+/** Shared collection; each faux provider gets a unique id so coexisting fakes route correctly. */
+const models = createModels();
+let fauxCount = 0;
+
+function createFauxModel(reasoning: boolean, maxTokens = 8192): { faux: FauxProviderHandle; model: Model<string> } {
+	const faux = fauxProvider({
+		provider: `faux-${++fauxCount}`,
 		models: [
 			{
 				id: reasoning ? "reasoning-model" : "non-reasoning-model",
@@ -135,18 +138,10 @@ function createFauxModel(
 			},
 		],
 	});
-	fauxRegistrations.push(faux);
+	models.setProvider(faux.provider);
 	return { faux, model: faux.getModel() };
 }
 
-const fauxRegistrations: FauxProviderRegistration[] = [];
-
-afterEach(() => {
-	while (fauxRegistrations.length > 0) {
-		fauxRegistrations.pop()?.unregister();
-	}
-});
-
 describe("harness compaction", () => {
 	beforeEach(() => {
 		nextId = 0;
@@ -306,11 +301,28 @@ describe("harness compaction", () => {
 				createMessageEntry({ ...assistant, stopReason: "error" }),
 			]),
 		).toBeUndefined();
+		expect(
+			getLastAssistantUsage([
+				createMessageEntry(createUserMessage("user")),
+				createMessageEntry(assistant),
+				createMessageEntry(createAssistantMessage("partial", createMockUsage(0, 0))),
+			]),
+		).toBe(usage);
 		expect(estimateContextTokens([createUserMessage("no usage")]).lastUsageIndex).toBeNull();
 		expect(estimateContextTokens([assistant, createUserMessage("tail")])).toMatchObject({
 			usageTokens: 20,
 			lastUsageIndex: 0,
 		});
+		const estimate = estimateContextTokens([
+			createUserMessage("Hello"),
+			assistant,
+			createUserMessage("continue"),
+			createAssistantMessage("Partial thinking", createMockUsage(0, 0)),
+		]);
+		expect(estimate.usageTokens).toBe(20);
+		expect(estimate.lastUsageIndex).toBe(1);
+		expect(estimate.trailingTokens).toBeGreaterThan(0);
+		expect(estimate.tokens).toBe(20 + estimate.trailingTokens);
 	});
 
 	it("builds session context with a compaction entry", () => {
@@ -445,19 +457,9 @@ describe("harness compaction", () => {
 			},
 		]);
 		getOrThrow(
-			await generateSummary(
-				messages,
-				reasoningModel,
-				2000,
-				"test-key",
-				undefined,
-				undefined,
-				undefined,
-				undefined,
-				"medium",
-			),
+			await generateSummary(messages, models, reasoningModel, 2000, undefined, undefined, undefined, "medium"),
 		);
-		expect(seenOptions[0]).toMatchObject({ reasoning: "medium", apiKey: "test-key" });
+		expect(seenOptions[0]).toMatchObject({ reasoning: "medium" });
 
 		const { faux: fauxOff, model: offModel } = createFauxModel(true);
 		fauxOff.setResponses([
@@ -466,9 +468,7 @@ describe("harness compaction", () => {
 				return fauxAssistantMessage("## Goal\nTest summary");
 			},
 		]);
-		getOrThrow(
-			await generateSummary(messages, offModel, 2000, "test-key", undefined, undefined, undefined, undefined, "off"),
-		);
+		getOrThrow(await generateSummary(messages, models, offModel, 2000, undefined, undefined, undefined, "off"));
 		expect(seenOptions[1]).not.toHaveProperty("reasoning");
 
 		const { faux: fauxNonReasoning, model: nonReasoningModel } = createFauxModel(false);
@@ -479,17 +479,7 @@ describe("harness compaction", () => {
 			},
 		]);
 		getOrThrow(
-			await generateSummary(
-				messages,
-				nonReasoningModel,
-				2000,
-				"test-key",
-				undefined,
-				undefined,
-				undefined,
-				undefined,
-				"medium",
-			),
+			await generateSummary(messages, models, nonReasoningModel, 2000, undefined, undefined, undefined, "medium"),
 		);
 		expect(seenOptions[2]).not.toHaveProperty("reasoning");
 	});
@@ -508,16 +498,7 @@ describe("harness compaction", () => {
 		]);
 
 		const summary = getOrThrow(
-			await generateSummary(
-				messages,
-				model,
-				2000,
-				"test-key",
-				{ "x-test": "yes" },
-				undefined,
-				"focus",
-				"old summary",
-			),
+			await generateSummary(messages, models, model, 2000, undefined, "focus", "old summary"),
 		);
 
 		expect(summary).toContain("Test summary");
@@ -529,7 +510,7 @@ describe("harness compaction", () => {
 		const messages: AgentMessage[] = [createUserMessage("Summarize this.")];
 		const { faux: errorFaux, model: errorModel } = createFauxModel(false);
 		errorFaux.setResponses([fauxAssistantMessage("", { stopReason: "error", errorMessage: "boom" })]);
-		const errorResult = await generateSummary(messages, errorModel, 2000, "test-key");
+		const errorResult = await generateSummary(messages, models, errorModel, 2000);
 		expect(errorResult).toMatchObject({
 			ok: false,
 			error: { code: "summarization_failed", message: "Summarization failed: boom" },
@@ -537,7 +518,7 @@ describe("harness compaction", () => {
 
 		const { faux: abortedFaux, model: abortedModel } = createFauxModel(false);
 		abortedFaux.setResponses([fauxAssistantMessage("", { stopReason: "aborted", errorMessage: "stopped" })]);
-		const abortedResult = await generateSummary(messages, abortedModel, 2000, "test-key");
+		const abortedResult = await generateSummary(messages, models, abortedModel, 2000);
 		expect(abortedResult).toMatchObject({ ok: false, error: { code: "aborted", message: "stopped" } });
 	});
 
@@ -565,7 +546,7 @@ describe("harness compaction", () => {
 			settings: { enabled: true, reserveTokens: 500000, keepRecentTokens: 20000 },
 		};
 
-		getOrThrow(await compact(preparation, model, "test-key"));
+		getOrThrow(await compact(preparation, models, model));
 
 		expect(seenOptions.map((options) => options?.maxTokens)).toEqual([128000, 128000]);
 	});
@@ -583,7 +564,7 @@ describe("harness compaction", () => {
 		};
 		const { faux: historyFaux, model: historyModel } = createFauxModel(false);
 		historyFaux.setResponses([fauxAssistantMessage("", { stopReason: "error", errorMessage: "history failed" })]);
-		expect(await compact(preparation, historyModel, "test-key")).toMatchObject({
+		expect(await compact(preparation, models, historyModel)).toMatchObject({
 			ok: false,
 			error: { code: "summarization_failed", message: "Summarization failed: history failed" },
 		});
@@ -591,8 +572,8 @@ describe("harness compaction", () => {
 		const { model: invalidModel } = createFauxModel(false);
 		const invalidResult = await compact(
 			{ ...preparation, messagesToSummarize: [], firstKeptEntryId: "" },
+			models,
 			invalidModel,
-			"test-key",
 		);
 		expect(invalidResult).toMatchObject({ ok: false, error: { code: "invalid_session" } });
 	});
@@ -617,7 +598,7 @@ describe("harness compaction", () => {
 			settings: { enabled: true, reserveTokens: 2000, keepRecentTokens: 20 },
 		};
 
-		getOrThrow(await compact(preparation, model, "test-key", undefined, undefined, undefined, "high"));
+		getOrThrow(await compact(preparation, models, model, undefined, undefined, "high"));
 
 		expect(seenOptions[0]).toMatchObject({ reasoning: "high" });
 	});
@@ -636,14 +617,14 @@ describe("harness compaction", () => {
 		const { faux, model } = createFauxModel(false);
 		faux.setResponses([fauxAssistantMessage("", { stopReason: "error", errorMessage: "prefix failed" })]);
 
-		expect(await compact(preparation, model, "test-key")).toMatchObject({
+		expect(await compact(preparation, models, model)).toMatchObject({
 			ok: false,
 			error: { code: "summarization_failed", message: "Turn prefix summarization failed: prefix failed" },
 		});
 
 		const { faux: abortedFaux, model: abortedModel } = createFauxModel(false);
 		abortedFaux.setResponses([fauxAssistantMessage("", { stopReason: "aborted", errorMessage: "prefix stopped" })]);
-		expect(await compact(preparation, abortedModel, "test-key")).toMatchObject({
+		expect(await compact(preparation, models, abortedModel)).toMatchObject({
 			ok: false,
 			error: { code: "aborted", message: "prefix stopped" },
 		});
@@ -662,7 +643,7 @@ describe("harness compaction", () => {
 		expect(preparation).toBeDefined();
 		const { faux, model } = createFauxModel(false);
 		faux.setResponses([fauxAssistantMessage("## Goal\nTest summary")]);
-		const result = getOrThrow(await compact(preparation!, model, "test-key"));
+		const result = getOrThrow(await compact(preparation!, models, model));
 		expect(result.summary.length).toBeGreaterThan(0);
 		expect(result.firstKeptEntryId).toBeTruthy();
 		expect(result.details).toBeDefined();

packages/agent/test/harness/repo.test.ts

@@ -65,4 +65,28 @@ describe("JsonlSessionRepo", () => {
 		expect(existsSync(sourceMetadata.path)).toBe(false);
 		await expect(repo.open(sourceMetadata)).rejects.toThrow("Session not found");
 	});
+
+	it("persists header metadata through create, list, and fork", async () => {
+		const root = createTempDir();
+		const env = new NodeExecutionEnv({ cwd: root });
+		const repo = new JsonlSessionRepo({ fs: env, sessionsRoot: root });
+		const source = await repo.create({
+			cwd: "/tmp/source",
+			id: "source-session",
+			metadata: { profile: "reviewer" },
+		});
+		const sourceMetadata = await source.getMetadata();
+		expect(sourceMetadata.metadata).toEqual({ profile: "reviewer" });
+		expect((await repo.list({ cwd: "/tmp/source" })).map((listed) => listed.metadata)).toEqual([
+			{ profile: "reviewer" },
+		]);
+		const fork = await repo.fork(sourceMetadata, { cwd: "/tmp/target", id: "fork-session" });
+		expect((await fork.getMetadata()).metadata).toEqual({ profile: "reviewer" });
+		const overridden = await repo.fork(sourceMetadata, {
+			cwd: "/tmp/target",
+			id: "overridden-session",
+			metadata: { profile: "writer" },
+		});
+		expect((await overridden.getMetadata()).metadata).toEqual({ profile: "writer" });
+	});
 });

packages/agent/test/harness/session.test.ts

@@ -4,10 +4,18 @@ import { describe, expect, it } from "vitest";
 import { NodeExecutionEnv } from "../../src/harness/env/nodejs.ts";
 import { JsonlSessionStorage } from "../../src/harness/session/jsonl-storage.ts";
 import { InMemorySessionStorage } from "../../src/harness/session/memory-storage.ts";
-import { Session } from "../../src/harness/session/session.ts";
+import { type ContextEntryTransform, Session } from "../../src/harness/session/session.ts";
 import type { SessionStorage } from "../../src/harness/types.ts";
 import { createAssistantMessage, createTempDir, createUserMessage, getLatestTempDir } from "./session-test-utils.ts";
 
+function getTextData(data: unknown): string {
+	if (typeof data !== "object" || data === null || !("text" in data)) {
+		return "";
+	}
+	const value = (data as { text?: unknown }).text;
+	return typeof value === "string" ? value : "";
+}
+
 async function runSessionSuite(
 	name: string,
 	createStorage: () => SessionStorage | Promise<SessionStorage>,
@@ -86,6 +94,51 @@ async function runSessionSuite(
 			expect(context.messages[1]?.role).toBe("custom");
 		});
 
+		it("keeps custom entries in context entries but omits them from messages by default", async () => {
+			const session = new Session(await createStorage());
+			await session.appendMessage(createUserMessage("one"));
+			await session.appendCustomEntry("chat_message", { text: "hello" });
+			const contextEntries = await session.buildContextEntries();
+			const context = await session.buildContext();
+			expect(contextEntries.map((entry) => entry.type)).toEqual(["message", "custom"]);
+			expect(context.messages).toHaveLength(1);
+		});
+
+		it("projects custom entries with configured custom-entry projectors", async () => {
+			const session = new Session(await createStorage(), {
+				entryProjectors: {
+					chat_message: (entry) => [createUserMessage(`chat: ${getTextData(entry.data)}`)],
+				},
+			});
+			await session.appendMessage(createUserMessage("one"));
+			await session.appendCustomEntry("chat_message", { text: "hello" });
+			const context = await session.buildContext();
+			expect(context.messages.map((message) => message.role)).toEqual(["user", "user"]);
+			expect(context.messages[1]).toMatchObject({ content: [{ type: "text", text: "chat: hello" }] });
+		});
+
+		it("applies context entry transforms after default compaction selection", async () => {
+			let observedFirstEntryType: string | undefined;
+			const dropCompaction: ContextEntryTransform = (entries) => {
+				observedFirstEntryType = entries[0]?.type;
+				return entries.filter((entry) => entry.type !== "compaction");
+			};
+			const session = new Session(await createStorage(), { entryTransforms: [dropCompaction] });
+			await session.appendMessage(createUserMessage("one"));
+			const kept = await session.appendMessage(createUserMessage("two"));
+			await session.appendCompaction("summary", kept, 1234);
+			await session.appendMessage(createUserMessage("three"));
+			const context = await session.buildContext();
+			expect(observedFirstEntryType).toBe("compaction");
+			expect(context.messages.map((message) => message.role)).toEqual(["user", "user"]);
+		});
+
+		it("normalizes session names", async () => {
+			const session = new Session(await createStorage());
+			await session.appendSessionName(" hello\nworld\r\nagain ");
+			expect(await session.getSessionName()).toBe("hello world again");
+		});
+
 		it("supports labels and session info entries without affecting context", async () => {
 			const session = new Session(await createStorage());
 			const user1 = await session.appendMessage(createUserMessage("one"));

packages/agent/test/harness/storage.test.ts

@@ -186,6 +186,48 @@ describe("JsonlSessionStorage", () => {
 		expect(await loadJsonlSessionMetadata(env, filePath)).toEqual(metadata);
 	});
 
+	it("round-trips custom header metadata", async () => {
+		const dir = createTempDir();
+		const env = new NodeExecutionEnv({ cwd: dir });
+		const filePath = join(dir, "session.jsonl");
+		const storage = await JsonlSessionStorage.create(env, filePath, {
+			cwd: dir,
+			sessionId: "session-1",
+			metadata: { profile: "reviewer" },
+		});
+		expect((await storage.getMetadata()).metadata).toEqual({ profile: "reviewer" });
+		const loaded = await JsonlSessionStorage.open(env, filePath);
+		expect((await loaded.getMetadata()).metadata).toEqual({ profile: "reviewer" });
+		expect((await loadJsonlSessionMetadata(env, filePath)).metadata).toEqual({ profile: "reviewer" });
+	});
+
+	it("omits header metadata when not provided", async () => {
+		const dir = createTempDir();
+		const env = new NodeExecutionEnv({ cwd: dir });
+		const filePath = join(dir, "session.jsonl");
+		await JsonlSessionStorage.create(env, filePath, { cwd: dir, sessionId: "session-1" });
+		expect(JSON.parse(readFileSync(filePath, "utf8").trim())).not.toHaveProperty("metadata");
+		expect((await loadJsonlSessionMetadata(env, filePath)).metadata).toBeUndefined();
+	});
+
+	it("throws for non-object header metadata", async () => {
+		const dir = createTempDir();
+		const env = new NodeExecutionEnv({ cwd: dir });
+		const filePath = join(dir, "session.jsonl");
+		const header = {
+			type: "session",
+			version: 3,
+			id: "session-1",
+			timestamp: "2026-01-01T00:00:00.000Z",
+			cwd: dir,
+			metadata: "profile",
+		};
+		writeFileSync(filePath, `${JSON.stringify(header)}\n`);
+		await expect(JsonlSessionStorage.open(env, filePath)).rejects.toThrow(
+			"session header metadata must be an object",
+		);
+	});
+
 	it("loads existing entries and reconstructs leaf", async () => {
 		const dir = createTempDir();
 		const env = new NodeExecutionEnv({ cwd: dir });

packages/agent/test/scratch/simple.ts

@@ -1,6 +1,8 @@
 import { homedir } from "node:os";
 import { join } from "node:path";
-import { getModel } from "@earendil-works/pi-ai";
+import { createModels } from "@earendil-works/pi-ai";
+import { cloudflareAIGatewayProvider } from "@earendil-works/pi-ai/providers/cloudflare-ai-gateway";
+import { openaiProvider } from "@earendil-works/pi-ai/providers/openai";
 import { NodeExecutionEnv } from "../../src/harness/env/nodejs.ts";
 import { InMemorySessionStorage } from "../../src/harness/session/memory-storage.ts";
 import {
@@ -35,11 +37,22 @@ const { promptTemplates: sourcedPromptTemplates } = await loadSourcedPromptTempl
 	(promptTemplate, source) => ({ ...promptTemplate, source }),
 );
 
+const models = createModels();
+models.setProvider(openaiProvider());
+models.setProvider(cloudflareAIGatewayProvider());
+const model = models.getModel("openai", "gpt-5.5");
+// const model = models.getModel("cloudflare-ai-gateway", "claude-haiku-4-5");
+if (!model) {
+	console.log("Model not found");
+	process.exit(-1);
+}
+
 const session = new Session(new InMemorySessionStorage());
 const agent = new AgentHarness({
 	env,
 	session,
-	model: getModel("openai", "gpt-5.5"),
+	models,
+	model,
 	thinkingLevel: "low",
 	systemPrompt: ({ env, resources }) =>
 		[

packages/agent/vitest.config.ts

@@ -1,15 +1,21 @@
+import { fileURLToPath } from "node:url";
 import { defineConfig } from "vitest/config";
 
+const aiSrcIndex = fileURLToPath(new URL("../ai/src/index.ts", import.meta.url));
+const aiSrcCompat = fileURLToPath(new URL("../ai/src/compat.ts", import.meta.url));
+
 export default defineConfig({
-	resolve: {
-		alias: {
-			"@earendil-works/pi-ai/base": new URL("../ai/src/base.ts", import.meta.url).pathname,
-			"@earendil-works/pi-ai": new URL("../ai/src/index.ts", import.meta.url).pathname,
-		},
-	},
 	test: {
 		globals: true,
 		environment: "node",
 		testTimeout: 30000, // 30 seconds for API calls
+		reporters: process.env.GITHUB_ACTIONS ? ["dot", "github-actions"] : ["dot"],
+		silent: "passed-only",
+	},
+	resolve: {
+		alias: [
+			{ find: /^@earendil-works\/pi-ai$/, replacement: aiSrcIndex },
+			{ find: /^@earendil-works\/pi-ai\/compat$/, replacement: aiSrcCompat },
+		],
 	},
 });

packages/agent/vitest.harness.config.ts

@@ -1,12 +1,10 @@
+import { fileURLToPath } from "node:url";
 import { defineConfig } from "vitest/config";
 
+const aiSrcIndex = fileURLToPath(new URL("../ai/src/index.ts", import.meta.url));
+const aiSrcCompat = fileURLToPath(new URL("../ai/src/compat.ts", import.meta.url));
+
 export default defineConfig({
-	resolve: {
-		alias: {
-			"@earendil-works/pi-ai/base": new URL("../ai/src/base.ts", import.meta.url).pathname,
-			"@earendil-works/pi-ai": new URL("../ai/src/index.ts", import.meta.url).pathname,
-		},
-	},
 	test: {
 		globals: true,
 		environment: "node",
@@ -21,4 +19,10 @@ export default defineConfig({
 			reportsDirectory: "coverage/harness",
 		},
 	},
+	resolve: {
+		alias: [
+			{ find: /^@earendil-works\/pi-ai$/, replacement: aiSrcIndex },
+			{ find: /^@earendil-works\/pi-ai\/compat$/, replacement: aiSrcCompat },
+		],
+	},
 });

packages/ai/CHANGELOG.md

@@ -1,5 +1,146 @@
 # Changelog
 
+## [Unreleased]
+
+### Fixed
+
+- Fixed Xiaomi Token Plan model metadata to follow the upstream models.dev token-plan catalogs, removing unsupported `mimo-v2-omni` variants ([#6204](https://github.com/earendil-works/pi/issues/6204)).
+- Fixed GitHub Copilot device-code login polling to wait before the first token poll, avoiding incorrect device-code failures for some users after browser authorization ([#6187](https://github.com/earendil-works/pi/issues/6187)).
+- Fixed OAuth device-code polling to honor the server-provided `slow_down` interval instead of only applying the RFC 8628 5-second increment, so GitHub Copilot login recovers instead of appearing to hang when polls arrive early (e.g. WSL/VM clock drift) ([#6187](https://github.com/earendil-works/pi/issues/6187)).
+- Fixed OpenAI Codex user-agent construction to synchronously load Node OS metadata, avoiding a startup race that could report `pi (browser)` in Node/Bun.
+- Fixed Fireworks GLM 5.2 Fast to use the OpenAI-compatible endpoint and `thinkingLevelMap`, aligning it with GLM 5.2 ([#6195](https://github.com/earendil-works/pi/issues/6195)).
+- Fixed Amazon Bedrock prompt-cache points for Claude Fable 5 and Claude Sonnet 5 ([#6235](https://github.com/earendil-works/pi/issues/6235)).
+- Fixed DS4 server context overflow detection for `Prompt has ... tokens, but the configured context size is ... tokens` errors ([#6262](https://github.com/earendil-works/pi/issues/6262)).
+- Fixed OpenAI Codex WebSocket sessions to rotate cached connections before the backend's 60-minute limit, avoiding connection-limit failures on long sessions ([#6268](https://github.com/earendil-works/pi/issues/6268)).
+- Fixed OpenAI Completions and Responses providers to send `(no tool output)` instead of `(see attached image)` when a tool result has empty text and no image content, preventing the model from hallucinating image attachments.
+- Fixed OpenAI Responses and Azure OpenAI Responses requests to avoid sending `max_output_tokens` values below the provider minimum ([#6265](https://github.com/earendil-works/pi/issues/6265)).
+- Fixed retry classification for Cloudflare 524 timeout responses ([#6239](https://github.com/earendil-works/pi/issues/6239)).
+- Fixed retry classification for Bun fetch socket-drop errors such as `socket connection was closed`, so transient stream disconnects retry automatically ([#6431](https://github.com/earendil-works/pi/issues/6431)).
+- Fixed GitHub Copilot extended context window models (Claude Opus 4.7/4.8, Claude Opus 4.6, Claude Sonnet 4.6/5, Claude Fable 5, GPT-5.3 Codex, GPT-5.4, GPT-5.5) to use `contextWindow: 1000000`, preventing premature compaction and under-budgeting ([#6439](https://github.com/earendil-works/pi/issues/6439)).
+
+### Added
+
+- Refreshed generated model catalogs from models.dev, adding newly listed models including Kimi K2.7 Code for GitHub Copilot and Fable 5 to several providers ([#6256](https://github.com/earendil-works/pi/issues/6256)).
+- Added Claude Sonnet 5 to the GitHub Copilot model catalog ([#6200](https://github.com/earendil-works/pi/issues/6200)).
+- Added zstd request-body compression for the OpenAI Codex Responses SSE transport. Requests are sent with `Content-Encoding: zstd` when Node/Bun zstd support is available; the WebSocket transport is unchanged.
+
+## [0.80.3] - 2026-06-30
+
+### Added
+
+- Added Anthropic Claude Sonnet 5 model metadata for Anthropic-compatible, Bedrock, OpenRouter, and Vercel AI Gateway providers.
+- Added Azure OpenAI Responses support for modern Microsoft Foundry endpoint URLs ([#6004](https://github.com/earendil-works/pi/pull/6004) by [@gukoff](https://github.com/gukoff)).
+- Added an optional `reasoning` field to `Usage` reporting reasoning/thinking token counts as a subset of `output`. Populated for Anthropic (`output_tokens_details.thinking_tokens`), OpenAI Responses/Codex/Azure (`output_tokens_details.reasoning_tokens`), OpenAI Completions (`completion_tokens_details.reasoning_tokens`), and Google Generative AI / Vertex (`thoughtsTokenCount`). Bedrock Converse and Mistral are not populated because those APIs do not return a reasoning token breakdown ([#6057](https://github.com/earendil-works/pi/issues/6057)).
+
+### Changed
+
+- Changed OpenAI Codex Responses SSE response-header waits to use the configured HTTP timeout instead of the previous fixed 20 second timeout, reducing false timeouts on slow connections ([#4945](https://github.com/earendil-works/pi/issues/4945)).
+
+### Fixed
+
+- Fixed Claude Sonnet 5 metadata to use adaptive thinking payloads for Anthropic-compatible and Bedrock requests.
+- Fixed generated Xiaomi MiMo model pricing to match current pay-as-you-go pricing from models.dev ([#6138](https://github.com/earendil-works/pi/issues/6138)).
+- Fixed provider HTTP errors to include response bodies instead of opaque SDK messages ([#5832](https://github.com/earendil-works/pi/pull/5832) by [@stephanmck](https://github.com/stephanmck)).
+- Fixed `streamSimple()` to send a context-aware max-token cap so providers that count input and output against one context window do not reject long requests ([#5595](https://github.com/earendil-works/pi/issues/5595)).
+- Fixed OpenAI Responses streams to preserve reasoning replay state when output items finish out of order ([#6009](https://github.com/earendil-works/pi/issues/6009)).
+- Fixed retry classification for provider errors that explicitly tell callers to retry the request ([#6019](https://github.com/earendil-works/pi/issues/6019)).
+- Fixed Z.AI preserved thinking requests to send `thinking.clear_thinking: false` when thinking is enabled, allowing replayed `reasoning_content` to participate in provider caching ([#6083](https://github.com/earendil-works/pi/issues/6083)).
+
+## [0.80.2] - 2026-06-23
+
+### Changed
+
+- Changed `ApiKeyCredential` to use the `auth.json`-compatible discriminator `type: "api_key"` and provider-scoped `env` values instead of `type: "api-key"` and metadata.
+
+### Fixed
+
+- Fixed Anthropic-compatible custom models to use explicit compatibility metadata instead of provider-name heuristics for session-affinity headers and unsupported tool-field omissions.
+- Fixed request-scoped `apiKey` and `env` values to participate in provider auth resolution, so providers such as Cloudflare can derive request-specific base URLs from explicit call options ([#6021](https://github.com/earendil-works/pi/issues/6021)).
+- Restored temporary legacy per-API stream aliases such as `streamSimpleOpenAICompletions` on the compat entrypoint ([#6016](https://github.com/earendil-works/pi/issues/6016), [#6017](https://github.com/earendil-works/pi/issues/6017)).
+- Restored runtime `detectCompat` fallback in `openai-completions` for models without explicit compat metadata ([#6020](https://github.com/earendil-works/pi/issues/6020)).
+
+## [0.80.1] - 2026-06-23
+
+### Fixed
+
+- Fixed a regression in Amazon Bedrock scoped `AWS_PROFILE` endpoint resolution for built-in inference profile endpoints.
+- Fixed Fireworks Anthropic-compatible requests to apply session-affinity and unsupported tool-field defaults for custom Fireworks models.
+- Fixed Together MiniMax M2.7 metadata to avoid unsupported Together reasoning toggles.
+
+## [0.80.0] - 2026-06-23
+
+### Breaking Changes
+
+- The root entrypoint (`@earendil-works/pi-ai`) is now core-only and side-effect free. The old global API moved to the temporary `@earendil-works/pi-ai/compat` entrypoint, a strict superset of the root: switching a file's import path is the only migration step. Moved symbols include `stream`/`complete`/`streamSimple`/`completeSimple`, `getModel`/`getModels`/`getProviders` (now deprecated aliases of `getBuiltinModel`/`getBuiltinModels`/`getBuiltinProviders` from `@earendil-works/pi-ai/providers/all`), `registerApiProvider`/`unregisterApiProviders`/`resetApiProviders`/`getApiProvider`, `getEnvApiKey`/`findEnvKeys`, `setBedrockProviderModule`, the per-API lazy stream wrappers (`anthropicMessagesApi`, ...), and the image-generation API.
+- Renamed the `Provider` type to `ProviderId`. `Provider` now names the runtime provider interface (id, name, auth, model listing, stream behavior).
+- API implementation modules moved from `src/providers/` to `@earendil-works/pi-ai/api/*`, renamed by API id (`anthropic` -> `api/anthropic-messages`, `google` -> `api/google-generative-ai`, `mistral` -> `api/mistral-conversations`, `amazon-bedrock` -> `api/bedrock-converse-stream`), each exporting exactly `stream` and `streamSimple`. The old per-impl export names (`streamAnthropic`, `streamSimpleAnthropic`, ...) and legacy raw API subpaths (`./anthropic`, `./google`, `./openai-completions`, ...) are gone; import raw API implementations through `@earendil-works/pi-ai/api/*`.
+- Removed the `@earendil-works/pi-ai/base` selective-provider entrypoint; use the root/core APIs with explicit `createModels()` collections and provider factories for isolated bundles.
+
+Migration guide:
+
+- Read `packages/ai/README.md` in full for the new `Models` API, provider factories, auth configuration, image generation, and custom provider examples.
+- To keep the old global API temporarily, change imports from `@earendil-works/pi-ai` to `@earendil-works/pi-ai/compat`. The compat entrypoint preserves `stream`/`complete`, generated catalog reads, API registry helpers, env API-key helpers, lazy API wrappers, and image globals, but it will be removed in a future release.
+- To migrate to the new runtime, create a `Models` collection and call methods on it:
+
+  ```ts
+  import { builtinModels } from "@earendil-works/pi-ai/providers/all";
+
+  const models = builtinModels();
+  const model = models.getModel("anthropic", "claude-haiku-4-5");
+  if (!model) throw new Error("model not found");
+
+  const message = await models.complete(model, {
+    messages: [{ role: "user", content: "Hello", timestamp: Date.now() }],
+  });
+  ```
+
+- For an isolated provider set, register provider factories explicitly:
+
+  ```ts
+  import { createModels } from "@earendil-works/pi-ai";
+  import { anthropicProvider } from "@earendil-works/pi-ai/providers/anthropic";
+
+  const models = createModels();
+  models.setProvider(anthropicProvider());
+  ```
+
+- To call a raw API implementation directly, import from `@earendil-works/pi-ai/api/*` and pass a compatible model plus auth/options yourself. Raw API modules export `stream` and `streamSimple`; use `.result()` on the returned stream for `complete`/`completeSimple` behavior:
+
+  ```ts
+  import { streamSimple } from "@earendil-works/pi-ai/api/anthropic-messages";
+  import { getBuiltinModel } from "@earendil-works/pi-ai/providers/all";
+
+  const model = getBuiltinModel("anthropic", "claude-haiku-4-5");
+  const stream = streamSimple(
+    model,
+    { messages: [{ role: "user", content: "Hello", timestamp: Date.now() }] },
+    { apiKey: process.env.ANTHROPIC_API_KEY },
+  );
+
+  const message = await stream.result();
+  ```
+
+  Custom raw models must set the matching `api` value (for example `"anthropic-messages"` for `api/anthropic-messages`) and any required provider compatibility metadata in `model.compat`.
+
+### Added
+
+- New `Models` runtime: `createModels()` builds an isolated provider collection with sync model reads (`getModels`/`getModel` return the last-known lists), an explicit async `refresh(provider?)` for dynamic providers, auth resolution (`getAuth`), and `stream`/`complete`/`streamSimple`/`completeSimple` that resolve auth through the owning provider. `createProvider()` builds providers from parts (single API implementation or a map dispatched on `model.api`; static `models` array plus an optional `refreshModels` fetcher with in-flight dedupe); `hasApi()` narrows dynamically listed models.
+- Provider auth substrate: `ProviderAuth` (`{ apiKey?, oauth? }`), one type-tagged credential per provider, `CredentialStore` (`read`/`modify`/`delete` with serialized writes; in-memory default), `envApiKeyAuth()`, `lazyOAuth()`, and injectable `AuthContext`. OAuth refresh runs under the store lock with double-checked expiry; a stored credential owns its provider (no silent env fallback).
+- One provider factory per built-in provider under `@earendil-works/pi-ai/providers/*` (e.g. `anthropicProvider()`, `openrouterProvider()`), plus `@earendil-works/pi-ai/providers/all` with `builtinProviders()`/`builtinModels()` and typed `getBuiltin*` catalog reads. Generated catalogs are split per provider, so importing one provider pulls one catalog; `sideEffects` metadata makes the package tree-shakeable.
+- OAuth flows (Anthropic, OpenAI Codex, GitHub Copilot) gained `OAuthAuth` adapters (`login`/`refresh`/`toAuth`) on unified `prompt()`/`notify()` login callbacks; Copilot's per-credential base URL is derived in `toAuth()`.
+- `fauxProvider()` returns a faux `Provider` for tests built on explicit `Models` collections.
+- Image generation mirrors the chat-side design: `createImagesModels()`/`ImagesProvider`/`createImagesProvider()` with sync model reads, explicit `refresh()`, provider-resolved auth, and never-rejecting `generateImages()`; `openrouterImagesProvider()` factory plus `builtinImagesProviders()`/`builtinImagesModels()` in `providers/all`. The `ImagesProvider` id type alias is renamed to `ImagesProviderId`; the old global image API stays on `/compat`.
+- Provider auth results can carry provider-scoped environment values that `Models` and `ImagesModels` merge into API implementation options.
+
+### Fixed
+
+- Fixed OpenAI Responses streams to fail when they end before a terminal response event and to treat `response.incomplete` as a length stop ([#5526](https://github.com/earendil-works/pi/pull/5526) by [@dmmulroy](https://github.com/dmmulroy)).
+- Fixed Amazon Bedrock endpoint resolution to honor scoped `AWS_PROFILE` values.
+- Fixed Cloudflare providers to require account/gateway configuration and route built-in `/compat` requests through provider auth.
+- Fixed `/compat` API-key injection to honor request-scoped `env` values.
+- Fixed OpenAI Codex Responses WebSocket sessions to reconnect once when OpenAI's connection limit is reached before output starts ([#5973](https://github.com/earendil-works/pi/issues/5973)).
+- Fixed OpenCode Go GLM-5.2 metadata to expose `xhigh` reasoning and send `reasoning_effort: "max"` ([#5967](https://github.com/earendil-works/pi/issues/5967)).
+
 ## [0.79.10] - 2026-06-22
 
 ### Fixed

packages/ai/package.json

@@ -1,58 +1,31 @@
 {
 	"name": "@earendil-works/pi-ai",
-	"version": "0.79.10",
+	"version": "0.80.3",
 	"description": "Unified LLM API with automatic model discovery and provider configuration",
 	"type": "module",
 	"main": "./dist/index.js",
 	"types": "./dist/index.d.ts",
+	"sideEffects": [
+		"./dist/compat.js",
+		"./dist/images.js",
+		"./dist/providers/images/register-builtins.js"
+	],
 	"exports": {
 		".": {
 			"types": "./dist/index.d.ts",
 			"import": "./dist/index.js"
 		},
-		"./base": {
-			"types": "./dist/base.d.ts",
-			"import": "./dist/base.js"
+		"./compat": {
+			"types": "./dist/compat.d.ts",
+			"import": "./dist/compat.js"
 		},
-		"./amazon-bedrock": {
-			"types": "./dist/providers/amazon-bedrock.d.ts",
-			"import": "./dist/providers/amazon-bedrock.js"
+		"./providers/*": {
+			"types": "./dist/providers/*.d.ts",
+			"import": "./dist/providers/*.js"
 		},
-		"./anthropic": {
-			"types": "./dist/providers/anthropic.d.ts",
-			"import": "./dist/providers/anthropic.js"
-		},
-		"./azure-openai-responses": {
-			"types": "./dist/providers/azure-openai-responses.d.ts",
-			"import": "./dist/providers/azure-openai-responses.js"
-		},
-		"./google": {
-			"types": "./dist/providers/google.d.ts",
-			"import": "./dist/providers/google.js"
-		},
-		"./google-vertex": {
-			"types": "./dist/providers/google-vertex.d.ts",
-			"import": "./dist/providers/google-vertex.js"
-		},
-		"./mistral": {
-			"types": "./dist/providers/mistral.d.ts",
-			"import": "./dist/providers/mistral.js"
-		},
-		"./openai-codex-responses": {
-			"types": "./dist/providers/openai-codex-responses.d.ts",
-			"import": "./dist/providers/openai-codex-responses.js"
-		},
-		"./openai-completions": {
-			"types": "./dist/providers/openai-completions.d.ts",
-			"import": "./dist/providers/openai-completions.js"
-		},
-		"./openai-responses": {
-			"types": "./dist/providers/openai-responses.d.ts",
-			"import": "./dist/providers/openai-responses.js"
-		},
-		"./openrouter-images": {
-			"types": "./dist/providers/images/openrouter.d.ts",
-			"import": "./dist/providers/images/openrouter.js"
+		"./api/*": {
+			"types": "./dist/api/*.d.ts",
+			"import": "./dist/api/*.js"
 		},
 		"./oauth": {
 			"types": "./dist/oauth.d.ts",

packages/ai/scripts/generate-models.ts

@@ -1,6 +1,6 @@
 #!/usr/bin/env node
 
-import { writeFileSync } from "fs";
+import { readdirSync, rmSync, writeFileSync } from "fs";
 import { join, dirname } from "path";
 import { fileURLToPath } from "url";
 import {
@@ -8,7 +8,7 @@ import {
 	CLOUDFLARE_AI_GATEWAY_COMPAT_BASE_URL,
 	CLOUDFLARE_AI_GATEWAY_OPENAI_BASE_URL,
 	CLOUDFLARE_WORKERS_AI_BASE_URL,
-} from "../src/providers/cloudflare.ts";
+} from "../src/api/cloudflare.ts";
 import type { AnthropicMessagesCompat, Api, KnownProvider, Model, OpenAICompletionsCompat } from "../src/types.ts";
 
 const __filename = fileURLToPath(import.meta.url);
@@ -68,8 +68,6 @@ const KIMI_STATIC_HEADERS = {
 	"User-Agent": "KimiCLI/1.5",
 } as const;
 
-const MOONSHOT_CN_MIRRORED_MODEL_IDS = new Set(["kimi-k2.7-code", "kimi-k2.7-code-highspeed"]);
-
 const TOGETHER_BASE_URL = "https://api.together.ai/v1";
 const TOGETHER_BASE_COMPAT: OpenAICompletionsCompat = {
 	supportsStore: false,
@@ -164,6 +162,14 @@ const ZAI_GLM52_THINKING_LEVEL_MAP = {
 	high: "high",
 	xhigh: "max",
 } as const;
+const OPENCODE_GO_GLM52_THINKING_LEVEL_MAP = {
+	off: null,
+	minimal: null,
+	low: null,
+	medium: null,
+	high: "high",
+	xhigh: "max",
+} as const;
 const EAGER_TOOL_INPUT_STREAMING_UNSUPPORTED_ANTHROPIC_MODELS = new Set([
 	"github-copilot:claude-haiku-4.5",
 	"github-copilot:claude-sonnet-4",
@@ -206,6 +212,20 @@ const OPENCODE_OPENAI_COMPLETIONS_LONG_CACHE_RETENTION_UNSUPPORTED_MODELS = new
 	"opencode-go:kimi-k2.6",
 ]);
 
+// GitHub's "Models with extended capabilities" table lists these Copilot models as supporting
+// the extended 1 million token context window.
+const GITHUB_COPILOT_EXTENDED_CONTEXT_MODELS = new Set([
+	"claude-fable-5",
+	"claude-opus-4.6",
+	"claude-opus-4.7",
+	"claude-opus-4.8",
+	"claude-sonnet-4.6",
+	"claude-sonnet-5",
+	"gpt-5.3-codex",
+	"gpt-5.4",
+	"gpt-5.5",
+]);
+
 // Checked manually against the authenticated GitHub Copilot /models endpoint on 2026-06-15.
 // Keep this to narrow corrections over models.dev metadata instead of snapshotting Copilot's catalog.
 const GITHUB_COPILOT_THINKING_LEVEL_OVERRIDES = {
@@ -260,6 +280,8 @@ function isAnthropicAdaptiveThinkingModel(modelId: string): boolean {
 		modelId.includes("opus-4.8") ||
 		modelId.includes("sonnet-4-6") ||
 		modelId.includes("sonnet-4.6") ||
+		modelId.includes("sonnet-5") ||
+		modelId.includes("sonnet.5") ||
 		modelId.includes("fable-5")
 	);
 }
@@ -269,10 +291,149 @@ function isAnthropicTemperatureUnsupportedModel(modelId: string): boolean {
 	return id.includes("opus-4-7") || id.includes("opus-4.7") || id.includes("opus-4-8") || id.includes("opus-4.8");
 }
 
+const OPENAI_COMPLETIONS_DEFAULT_COMPAT = {
+	supportsStore: true,
+	supportsDeveloperRole: true,
+	supportsReasoningEffort: true,
+	supportsUsageInStreaming: true,
+	maxTokensField: "max_completion_tokens",
+	requiresToolResultName: false,
+	requiresAssistantAfterToolResult: false,
+	requiresThinkingAsText: false,
+	requiresReasoningContentOnAssistantMessages: false,
+	thinkingFormat: "openai",
+	openRouterRouting: {},
+	vercelGatewayRouting: {},
+	chatTemplateKwargs: {},
+	zaiToolStream: false,
+	supportsStrictMode: true,
+	sendSessionAffinityHeaders: false,
+	supportsLongCacheRetention: true,
+} satisfies Required<Omit<OpenAICompletionsCompat, "cacheControlFormat">> & {
+	cacheControlFormat?: OpenAICompletionsCompat["cacheControlFormat"];
+};
+
+type OpenAICompletionsResolvedCompat = typeof OPENAI_COMPLETIONS_DEFAULT_COMPAT & {
+	cacheControlFormat?: OpenAICompletionsCompat["cacheControlFormat"];
+};
+
 function mergeAnthropicMessagesCompat(model: Model<Api>, compat: AnthropicMessagesCompat): void {
 	model.compat = { ...(model.compat as AnthropicMessagesCompat | undefined), ...compat };
 }
 
+function detectOpenAICompletionsCompat(model: Model<"openai-completions">): OpenAICompletionsResolvedCompat {
+	const provider = model.provider;
+	const baseUrl = model.baseUrl;
+
+	const isZai =
+		provider === "zai" ||
+		provider === "zai-coding-cn" ||
+		baseUrl.includes("api.z.ai") ||
+		baseUrl.includes("open.bigmodel.cn");
+	const isTogether =
+		provider === "together" || baseUrl.includes("api.together.ai") || baseUrl.includes("api.together.xyz");
+	const isMoonshot = provider === "moonshotai" || provider === "moonshotai-cn" || baseUrl.includes("api.moonshot.");
+	const isOpenRouter = provider === "openrouter" || baseUrl.includes("openrouter.ai");
+	const isCloudflareWorkersAI = provider === "cloudflare-workers-ai" || baseUrl.includes("api.cloudflare.com");
+	const isCloudflareAiGateway = provider === "cloudflare-ai-gateway" || baseUrl.includes("gateway.ai.cloudflare.com");
+	const isNvidia = provider === "nvidia" || baseUrl.includes("integrate.api.nvidia.com");
+	const isAntLing = provider === "ant-ling" || baseUrl.includes("api.ant-ling.com");
+	const isTogetherReasoningOnly = isTogether && TOGETHER_REASONING_ONLY_MODELS.has(model.id);
+
+	const isNonStandard =
+		isNvidia ||
+		provider === "cerebras" ||
+		baseUrl.includes("cerebras.ai") ||
+		provider === "xai" ||
+		baseUrl.includes("api.x.ai") ||
+		isTogether ||
+		baseUrl.includes("chutes.ai") ||
+		baseUrl.includes("deepseek.com") ||
+		isZai ||
+		isMoonshot ||
+		provider === "opencode" ||
+		baseUrl.includes("opencode.ai") ||
+		isCloudflareWorkersAI ||
+		isCloudflareAiGateway ||
+		isAntLing;
+
+	const useMaxTokens =
+		baseUrl.includes("chutes.ai") || isMoonshot || isCloudflareAiGateway || isTogether || isNvidia || isAntLing;
+
+	const isGrok = provider === "xai" || baseUrl.includes("api.x.ai");
+	const isDeepSeek = provider === "deepseek" || baseUrl.includes("deepseek.com");
+	const isOpenRouterDeveloperRoleModel =
+		isOpenRouter && (model.id.startsWith("anthropic/") || model.id.startsWith("openai/"));
+	const cacheControlFormat = provider === "openrouter" && model.id.startsWith("anthropic/") ? "anthropic" : undefined;
+
+	return {
+		supportsStore: !isNonStandard,
+		supportsDeveloperRole: isOpenRouterDeveloperRoleModel || (!isNonStandard && !isOpenRouter),
+		supportsReasoningEffort:
+			!isGrok && !isZai && !isMoonshot && !isTogether && !isCloudflareAiGateway && !isNvidia && !isAntLing,
+		supportsUsageInStreaming: true,
+		maxTokensField: useMaxTokens ? "max_tokens" : "max_completion_tokens",
+		requiresToolResultName: false,
+		requiresAssistantAfterToolResult: false,
+		requiresThinkingAsText: false,
+		requiresReasoningContentOnAssistantMessages: isDeepSeek,
+		thinkingFormat: isDeepSeek
+			? "deepseek"
+			: isZai
+				? "zai"
+				: isTogether && !isTogetherReasoningOnly
+					? "together"
+					: isAntLing
+						? "ant-ling"
+						: isOpenRouter
+							? "openrouter"
+							: "openai",
+		openRouterRouting: {},
+		vercelGatewayRouting: {},
+		chatTemplateKwargs: {},
+		zaiToolStream: false,
+		supportsStrictMode: !isMoonshot && !isTogether && !isCloudflareAiGateway && !isNvidia,
+		...(cacheControlFormat ? { cacheControlFormat } : {}),
+		sendSessionAffinityHeaders: false,
+		supportsLongCacheRetention: !(
+			isTogether ||
+			isCloudflareWorkersAI ||
+			isCloudflareAiGateway ||
+			isNvidia ||
+			isAntLing
+		),
+	};
+}
+
+function isPlainEmptyObject(value: unknown): boolean {
+	return typeof value === "object" && value !== null && !Array.isArray(value) && Object.keys(value).length === 0;
+}
+
+function openAICompletionsCompatDelta(compat: OpenAICompletionsResolvedCompat): OpenAICompletionsCompat {
+	const delta: OpenAICompletionsCompat = {};
+	for (const [key, value] of Object.entries(compat)) {
+		const defaultValue = OPENAI_COMPLETIONS_DEFAULT_COMPAT[key as keyof typeof OPENAI_COMPLETIONS_DEFAULT_COMPAT];
+		if (isPlainEmptyObject(value) && isPlainEmptyObject(defaultValue)) continue;
+		if (value !== defaultValue) {
+			(delta as Record<string, unknown>)[key] = value;
+		}
+	}
+	return delta;
+}
+
+function mergeOpenAICompletionsCompat(model: Model<Api>, compat: OpenAICompletionsCompat): void {
+	model.compat = { ...(model.compat as OpenAICompletionsCompat | undefined), ...compat };
+}
+
+function applyOpenAICompletionsCompatMetadata(model: Model<Api>): void {
+	if (model.api !== "openai-completions") return;
+	const detected = openAICompletionsCompatDelta(detectOpenAICompletionsCompat(model as Model<"openai-completions">));
+	model.compat = { ...detected, ...(model.compat as OpenAICompletionsCompat | undefined) };
+	if (Object.keys(model.compat).length === 0) {
+		delete model.compat;
+	}
+}
+
 function isGemini3ProModel(modelId: string): boolean {
 	return /gemini-3(?:\.\d+)?-pro/.test(modelId.toLowerCase());
 }
@@ -377,9 +538,12 @@ function applyThinkingLevelMetadata(model: Model<any>): void {
 	if (model.provider === "openrouter" && model.id === "z-ai/glm-5.2") {
 		mergeThinkingLevelMap(model, { xhigh: "xhigh" });
 	}
-	if (model.provider === "fireworks" && model.id === "accounts/fireworks/models/glm-5p2") {
+	if (model.provider === "fireworks" && model.id.includes("glm-5p2")) {
 		mergeThinkingLevelMap(model, { off: "none", minimal: null, low: "high", medium: "high", xhigh: "max" });
 	}
+	if (model.provider === "opencode-go" && model.id === "glm-5.2") {
+		mergeThinkingLevelMap(model, OPENCODE_GO_GLM52_THINKING_LEVEL_MAP);
+	}
 	if (model.provider === "opencode-go" && model.id === "kimi-k2.6") {
 		// OpenCode Go exposes Kimi K2.6 thinking as on/off, not distinct effort tiers.
 		mergeThinkingLevelMap(model, { minimal: null, low: null, medium: null });
@@ -843,9 +1007,10 @@ async function loadModelsDevData(): Promise<Model<any>[]> {
 					continue;
 				}
 
-				// workers-ai/* through the gateway forwards x-session-affinity to
-				// the underlying Workers AI runtime for prefix-cache routing.
-				const compat = upstream === "workers-ai" ? { sendSessionAffinityHeaders: true } : undefined;
+				// Gateway passthroughs forward session affinity headers to upstreams that
+				// use them for cache/routing affinity.
+				const compat =
+					upstream === "anthropic" || upstream === "workers-ai" ? { sendSessionAffinityHeaders: true } : undefined;
 
 				models.push({
 					id,
@@ -1208,12 +1373,12 @@ async function loadModelsDevData(): Promise<Model<any>[]> {
 				if (m.tool_call !== true) continue;
 				if (m.status === "deprecated") continue;
 
-				// Claude 4.x models route to Anthropic Messages API
-				const isCopilotClaude4 = /^claude-(haiku|sonnet|opus)-4([.\-]|$)/.test(modelId);
+				// Claude 4.x and 5.x models route to Anthropic Messages API
+				const isCopilotClaude = /^claude-(haiku|sonnet|opus)-[45]([.\-]|$)/.test(modelId);
 				// gpt-5 models require responses API, others use completions
 				const needsResponsesApi = modelId.startsWith("gpt-5") || modelId.startsWith("oswe");
 
-				const api: Api = isCopilotClaude4
+				const api: Api = isCopilotClaude
 					? "anthropic-messages"
 					: needsResponsesApi
 						? "openai-responses"
@@ -1349,16 +1514,6 @@ async function loadModelsDevData(): Promise<Model<any>[]> {
 			"moonshotai-cn": getMoonshotProviderModels("moonshotai-cn"),
 		};
 
-		// models.dev can lag the CN catalog while the global Moonshot catalog already
-		// has the model. Mirror selected current model IDs into moonshotai-cn until
-		// upstream CN metadata catches up.
-		for (const modelId of MOONSHOT_CN_MIRRORED_MODEL_IDS) {
-			const model = moonshotModels.moonshotai[modelId];
-			if (model && !moonshotModels["moonshotai-cn"][modelId]) {
-				moonshotModels["moonshotai-cn"][modelId] = model;
-			}
-		}
-
 		for (const { key, provider, baseUrl } of moonshotVariants) {
 			for (const [modelId, m] of Object.entries(moonshotModels[key])) {
 				if (m.tool_call !== true) continue;
@@ -1393,38 +1548,50 @@ async function loadModelsDevData(): Promise<Model<any>[]> {
 			thinkingFormat: "deepseek",
 		};
 		const xiaomiVariants = [
-			{ provider: "xiaomi", baseUrl: "https://api.xiaomimimo.com/v1" },
-			{ provider: "xiaomi-token-plan-cn", baseUrl: "https://token-plan-cn.xiaomimimo.com/v1" },
-			{ provider: "xiaomi-token-plan-ams", baseUrl: "https://token-plan-ams.xiaomimimo.com/v1" },
-			{ provider: "xiaomi-token-plan-sgp", baseUrl: "https://token-plan-sgp.xiaomimimo.com/v1" },
+			{ source: "xiaomi", provider: "xiaomi", baseUrl: "https://api.xiaomimimo.com/v1" },
+			{
+				source: "xiaomi-token-plan-cn",
+				provider: "xiaomi-token-plan-cn",
+				baseUrl: "https://token-plan-cn.xiaomimimo.com/v1",
+			},
+			{
+				source: "xiaomi-token-plan-ams",
+				provider: "xiaomi-token-plan-ams",
+				baseUrl: "https://token-plan-ams.xiaomimimo.com/v1",
+			},
+			{
+				source: "xiaomi-token-plan-sgp",
+				provider: "xiaomi-token-plan-sgp",
+				baseUrl: "https://token-plan-sgp.xiaomimimo.com/v1",
+			},
 		] as const;
 
-		if (data.xiaomi?.models) {
-			for (const { provider, baseUrl } of xiaomiVariants) {
-				for (const [modelId, model] of Object.entries(data.xiaomi.models)) {
-					const m = model as ModelsDevModel;
-					if (m.tool_call !== true) continue;
-					if (provider.startsWith("xiaomi-token-plan-") && modelId === "mimo-v2-flash") continue;
+		for (const { source, provider, baseUrl } of xiaomiVariants) {
+			const providerModels = data[source]?.models;
+			if (!providerModels) continue;
 
-					models.push({
-						id: modelId,
-						name: m.name || modelId,
-						api: "openai-completions",
-						provider,
-						baseUrl,
-						compat: xiaomiCompat,
-						reasoning: m.reasoning === true,
-						input: m.modalities?.input?.includes("image") ? ["text", "image"] : ["text"],
-						cost: {
-							input: m.cost?.input || 0,
-							output: m.cost?.output || 0,
-							cacheRead: m.cost?.cache_read || 0,
-							cacheWrite: m.cost?.cache_write || 0,
-						},
-						contextWindow: m.limit?.context || 4096,
-						maxTokens: m.limit?.output || 4096,
-					});
-				}
+			for (const [modelId, model] of Object.entries(providerModels)) {
+				const m = model as ModelsDevModel;
+				if (m.tool_call !== true) continue;
+
+				models.push({
+					id: modelId,
+					name: m.name || modelId,
+					api: "openai-completions",
+					provider,
+					baseUrl,
+					compat: xiaomiCompat,
+					reasoning: m.reasoning === true,
+					input: m.modalities?.input?.includes("image") ? ["text", "image"] : ["text"],
+					cost: {
+						input: m.cost?.input || 0,
+						output: m.cost?.output || 0,
+						cacheRead: m.cost?.cache_read || 0,
+						cacheWrite: m.cost?.cache_write || 0,
+					},
+					contextWindow: m.limit?.context || 4096,
+					maxTokens: m.limit?.output || 4096,
+				});
 			}
 		}
 
@@ -1451,25 +1618,16 @@ async function generateModels() {
 			!((model.provider === "opencode" || model.provider === "opencode-go") && model.id === "gpt-5.3-codex-spark"),
 	);
 
-	// Fix incorrect cache pricing for Claude Opus 4.5 from models.dev
-	// models.dev has 3x the correct pricing (1.5/18.75 instead of 0.5/6.25)
-	const opus45 = allModels.find(m => m.provider === "anthropic" && m.id === "claude-opus-4-5");
-	if (opus45) {
-		opus45.cost.cacheRead = 0.5;
-		opus45.cost.cacheWrite = 6.25;
-	}
-
 	// Temporary overrides until upstream model metadata is corrected.
 	for (const candidate of allModels) {
-		if (candidate.provider === "amazon-bedrock" && candidate.id.includes("anthropic.claude-opus-4-6-v1")) {
-			candidate.cost.cacheRead = 0.5;
-			candidate.cost.cacheWrite = 6.25;
+		if (candidate.provider === "github-copilot" && GITHUB_COPILOT_EXTENDED_CONTEXT_MODELS.has(candidate.id)) {
+			candidate.contextWindow = 1000000;
 		}
+
 		if (
 			(candidate.provider === "anthropic" ||
 				candidate.provider === "opencode" ||
-				candidate.provider === "opencode-go" ||
-				candidate.provider === "github-copilot") &&
+				candidate.provider === "opencode-go") &&
 			(candidate.id === "claude-opus-4-6" ||
 				candidate.id === "claude-sonnet-4-6" ||
 				candidate.id === "claude-opus-4.6" ||
@@ -1517,7 +1675,7 @@ async function generateModels() {
 			candidate.cost.output = 1.9;
 			candidate.cost.cacheRead = 0.119;
 		}
-		if (candidate.provider === "fireworks" && candidate.id === "accounts/fireworks/models/glm-5p2") {
+		if (candidate.provider === "fireworks" && candidate.id.includes("glm-5p2")) {
 			candidate.api = "openai-completions";
 			candidate.baseUrl = "https://api.fireworks.ai/inference/v1";
 			candidate.compat = { supportsStore: false, supportsDeveloperRole: false };
@@ -1525,132 +1683,6 @@ async function generateModels() {
 	}
 
 
-	// Add missing EU Opus 4.6 profile
-	if (!allModels.some((m) => m.provider === "amazon-bedrock" && m.id === "eu.anthropic.claude-opus-4-6-v1")) {
-		allModels.push({
-			id: "eu.anthropic.claude-opus-4-6-v1",
-			name: "Claude Opus 4.6 (EU)",
-			api: "bedrock-converse-stream",
-			provider: "amazon-bedrock",
-			baseUrl: getBedrockBaseUrl("eu.anthropic.claude-opus-4-6-v1"),
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 5,
-				output: 25,
-				cacheRead: 0.5,
-				cacheWrite: 6.25,
-			},
-			contextWindow: 200000,
-			maxTokens: 128000,
-		});
-	}
-
-	// Add missing Claude Opus 4.6
-	if (!allModels.some(m => m.provider === "anthropic" && m.id === "claude-opus-4-6")) {
-		allModels.push({
-			id: "claude-opus-4-6",
-			name: "Claude Opus 4.6",
-			api: "anthropic-messages",
-			baseUrl: "https://api.anthropic.com",
-			provider: "anthropic",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 5,
-				output: 25,
-				cacheRead: 0.5,
-				cacheWrite: 6.25,
-			},
-			contextWindow: 1000000,
-			maxTokens: 128000,
-		});
-	}
-
-	// Add missing Claude Opus 4.7
-	if (!allModels.some(m => m.provider === "anthropic" && m.id === "claude-opus-4-7")) {
-		allModels.push({
-			id: "claude-opus-4-7",
-			name: "Claude Opus 4.7",
-			api: "anthropic-messages",
-			baseUrl: "https://api.anthropic.com",
-			provider: "anthropic",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 5,
-				output: 25,
-				cacheRead: 0.5,
-				cacheWrite: 6.25,
-			},
-			contextWindow: 1000000,
-			maxTokens: 128000,
-		});
-	}
-
-	// Add missing Claude Opus 4.8
-	if (!allModels.some(m => m.provider === "anthropic" && m.id === "claude-opus-4-8")) {
-		allModels.push({
-			id: "claude-opus-4-8",
-			name: "Claude Opus 4.8",
-			api: "anthropic-messages",
-			baseUrl: "https://api.anthropic.com",
-			provider: "anthropic",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 5,
-				output: 25,
-				cacheRead: 0.5,
-				cacheWrite: 6.25,
-			},
-			contextWindow: 1000000,
-			maxTokens: 128000,
-		});
-	}
-
-	// Add missing Claude Sonnet 4.6
-	if (!allModels.some(m => m.provider === "anthropic" && m.id === "claude-sonnet-4-6")) {
-		allModels.push({
-			id: "claude-sonnet-4-6",
-			name: "Claude Sonnet 4.6",
-			api: "anthropic-messages",
-			baseUrl: "https://api.anthropic.com",
-			provider: "anthropic",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 3,
-				output: 15,
-				cacheRead: 0.3,
-				cacheWrite: 3.75,
-			},
-			contextWindow: 1000000,
-			maxTokens: 64000,
-		});
-	}
-
-	// Add missing Gemini 3.1 Flash Lite Preview until models.dev includes it.
-	if (!allModels.some((m) => m.provider === "google" && m.id === "gemini-3.1-flash-lite-preview")) {
-		allModels.push({
-			id: "gemini-3.1-flash-lite-preview",
-			name: "Gemini 3.1 Flash Lite Preview",
-			api: "google-generative-ai",
-			baseUrl: "https://generativelanguage.googleapis.com/v1beta",
-			provider: "google",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 0,
-				output: 0,
-				cacheRead: 0,
-				cacheWrite: 0,
-			},
-			contextWindow: 1048576,
-			maxTokens: 65536,
-		});
-	}
-
 	// Add missing gpt models
 	if (!allModels.some(m => m.provider === "openai" && m.id === "gpt-5-chat-latest")) {
 		allModels.push({
@@ -1672,100 +1704,6 @@ async function generateModels() {
 		});
 	}
 
-	if (!allModels.some(m => m.provider === "openai" && m.id === "gpt-5.1-codex")) {
-		allModels.push({
-			id: "gpt-5.1-codex",
-			name: "GPT-5.1 Codex",
-			api: "openai-responses",
-			baseUrl: "https://api.openai.com/v1",
-			provider: "openai",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 1.25,
-				output: 5,
-				cacheRead: 0.125,
-				cacheWrite: 1.25,
-			},
-			contextWindow: 400000,
-			maxTokens: 128000,
-		});
-	}
-
-	if (!allModels.some(m => m.provider === "openai" && m.id === "gpt-5.1-codex-max")) {
-		allModels.push({
-			id: "gpt-5.1-codex-max",
-			name: "GPT-5.1 Codex Max",
-			api: "openai-responses",
-			baseUrl: "https://api.openai.com/v1",
-			provider: "openai",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 1.25,
-				output: 10,
-				cacheRead: 0.125,
-				cacheWrite: 0,
-			},
-			contextWindow: 400000,
-			maxTokens: 128000,
-		});
-	}
-
-	if (!allModels.some(m => m.provider === "openai" && m.id === "gpt-5.3-codex-spark")) {
-		allModels.push({
-			id: "gpt-5.3-codex-spark",
-			name: "GPT-5.3 Codex Spark",
-			api: "openai-responses",
-			baseUrl: "https://api.openai.com/v1",
-			provider: "openai",
-			reasoning: true,
-			input: ["text"],
-			cost: {
-				input: 0,
-				output: 0,
-				cacheRead: 0,
-				cacheWrite: 0,
-			},
-			contextWindow: 128000,
-			maxTokens: 16384,
-		});
-	}
-
-	// Add missing GitHub Copilot GPT-5.3 models until models.dev includes them.
-	const copilotBaseModel = allModels.find(
-		(m) => m.provider === "github-copilot" && m.id === "gpt-5.2-codex",
-	);
-	if (copilotBaseModel) {
-		if (!allModels.some((m) => m.provider === "github-copilot" && m.id === "gpt-5.3-codex")) {
-			allModels.push({
-				...copilotBaseModel,
-				id: "gpt-5.3-codex",
-				name: "GPT-5.3 Codex",
-			});
-		}
-	}
-
-	if (!allModels.some((m) => m.provider === "openai" && m.id === "gpt-5.4")) {
-		allModels.push({
-			id: "gpt-5.4",
-			name: "GPT-5.4",
-			api: "openai-responses",
-			baseUrl: "https://api.openai.com/v1",
-			provider: "openai",
-			reasoning: true,
-			input: ["text", "image"],
-			cost: {
-				input: 2.5,
-				output: 15,
-				cacheRead: 0.25,
-				cacheWrite: 0,
-			},
-			contextWindow: 272000,
-			maxTokens: 128000,
-		});
-	}
-
 	const deepseekCompat: OpenAICompletionsCompat = {
 		requiresReasoningContentOnAssistantMessages: true,
 		thinkingFormat: "deepseek",
@@ -2085,6 +2023,7 @@ async function generateModels() {
 
 	for (const model of allModels) {
 		applyThinkingLevelMetadata(model);
+		applyOpenAICompletionsCompatMetadata(model);
 	}
 
 	// Group by provider and deduplicate by model ID
@@ -2100,62 +2039,80 @@ async function generateModels() {
 		}
 	}
 
-	// Generate TypeScript file
-	let output = `// This file is auto-generated by scripts/generate-models.ts
+	// Generate TypeScript files: one catalog per provider plus an aggregator
+	const generatedHeader = `// This file is auto-generated by scripts/generate-models.ts
 // Do not edit manually - run 'npm run generate-models' to update
 
-import type { Model } from "./types.ts";
-
-export const MODELS = {
 `;
+	const catalogConstName = (providerId: string) => `${providerId.toUpperCase().replace(/[^A-Z0-9]+/g, "_")}_MODELS`;
 
-	// Generate provider sections (sorted for deterministic output)
-	const sortedProviderIds = Object.keys(providers).sort();
-	for (const providerId of sortedProviderIds) {
-		const models = providers[providerId];
-		output += `\t${JSON.stringify(providerId)}: {\n`;
-
-		const sortedModelIds = Object.keys(models).sort();
-		for (const modelId of sortedModelIds) {
-			const model = models[modelId];
-			output += `\t\t"${model.id}": {\n`;
-			output += `\t\t\tid: "${model.id}",\n`;
-			output += `\t\t\tname: "${model.name}",\n`;
-			output += `\t\t\tapi: "${model.api}",\n`;
-			output += `\t\t\tprovider: "${model.provider}",\n`;
-			if (model.baseUrl !== undefined) {
-				output += `\t\t\tbaseUrl: "${model.baseUrl}",\n`;
-			}
-			if (model.headers) {
-				output += `\t\t\theaders: ${JSON.stringify(model.headers)},\n`;
-			}
-			if (model.compat) {
-				output += `			compat: ${JSON.stringify(model.compat)},
-`;
-			}
-			output += `\t\t\treasoning: ${model.reasoning},\n`;
-			if (model.thinkingLevelMap) {
-				output += `\t\t\tthinkingLevelMap: ${JSON.stringify(model.thinkingLevelMap)},\n`;
-			}
-			output += `\t\t\tinput: [${model.input.map(i => `"${i}"`).join(", ")}],\n`;
-			output += `\t\t\tcost: {\n`;
-			output += `\t\t\t\tinput: ${model.cost.input},\n`;
-			output += `\t\t\t\toutput: ${model.cost.output},\n`;
-			output += `\t\t\t\tcacheRead: ${model.cost.cacheRead},\n`;
-			output += `\t\t\t\tcacheWrite: ${model.cost.cacheWrite},\n`;
-			output += `\t\t\t},\n`;
-			output += `\t\t\tcontextWindow: ${model.contextWindow},\n`;
-			output += `\t\t\tmaxTokens: ${model.maxTokens},\n`;
-			output += `\t\t} satisfies Model<"${model.api}">,\n`;
+	function emitModel(model: Model<any>, indent: string): string {
+		let output = `${indent}"${model.id}": {\n`;
+		output += `${indent}\tid: "${model.id}",\n`;
+		output += `${indent}\tname: "${model.name}",\n`;
+		output += `${indent}\tapi: "${model.api}",\n`;
+		output += `${indent}\tprovider: "${model.provider}",\n`;
+		if (model.baseUrl !== undefined) {
+			output += `${indent}\tbaseUrl: "${model.baseUrl}",\n`;
 		}
-
-		output += `\t},\n`;
+		if (model.headers) {
+			output += `${indent}\theaders: ${JSON.stringify(model.headers)},\n`;
+		}
+		if (model.compat) {
+			output += `${indent}\tcompat: ${JSON.stringify(model.compat)},\n`;
+		}
+		output += `${indent}\treasoning: ${model.reasoning},\n`;
+		if (model.thinkingLevelMap) {
+			output += `${indent}\tthinkingLevelMap: ${JSON.stringify(model.thinkingLevelMap)},\n`;
+		}
+		output += `${indent}\tinput: [${model.input.map(i => `"${i}"`).join(", ")}],\n`;
+		output += `${indent}\tcost: {\n`;
+		output += `${indent}\t\tinput: ${model.cost.input},\n`;
+		output += `${indent}\t\toutput: ${model.cost.output},\n`;
+		output += `${indent}\t\tcacheRead: ${model.cost.cacheRead},\n`;
+		output += `${indent}\t\tcacheWrite: ${model.cost.cacheWrite},\n`;
+		output += `${indent}\t},\n`;
+		output += `${indent}\tcontextWindow: ${model.contextWindow},\n`;
+		output += `${indent}\tmaxTokens: ${model.maxTokens},\n`;
+		output += `${indent}} satisfies Model<"${model.api}">,\n`;
+		return output;
 	}
 
-	output += `} as const;
-`;
+	const sortedProviderIds = Object.keys(providers).sort();
+	const providersDir = join(packageRoot, "src/providers");
 
-	// Write file
+	// Remove stale per-provider catalogs
+	for (const entry of readdirSync(providersDir)) {
+		if (entry.endsWith(".models.ts")) {
+			rmSync(join(providersDir, entry));
+		}
+	}
+
+	// Per-provider catalogs (sorted for deterministic output)
+	for (const providerId of sortedProviderIds) {
+		const models = providers[providerId];
+		let output = generatedHeader;
+		output += `import type { Model } from "../types.ts";\n\n`;
+		output += `export const ${catalogConstName(providerId)} = {\n`;
+		const sortedModelIds = Object.keys(models).sort();
+		for (const modelId of sortedModelIds) {
+			output += emitModel(models[modelId], "\t");
+		}
+		output += `} as const;\n`;
+		writeFileSync(join(providersDir, `${providerId}.models.ts`), output);
+	}
+	console.log(`Generated ${sortedProviderIds.length} catalogs under src/providers/`);
+
+	// Aggregator
+	let output = generatedHeader;
+	for (const providerId of sortedProviderIds) {
+		output += `import { ${catalogConstName(providerId)} } from "./providers/${providerId}.models.ts";\n`;
+	}
+	output += `\nexport const MODELS = {\n`;
+	for (const providerId of sortedProviderIds) {
+		output += `\t${JSON.stringify(providerId)}: ${catalogConstName(providerId)},\n`;
+	}
+	output += `} as const;\n`;
 	writeFileSync(join(packageRoot, "src/models.generated.ts"), output);
 	console.log("Generated src/models.generated.ts");
 

packages/ai/src/api-registry.ts

@@ -1,98 +0,0 @@
-import type {
-	Api,
-	AssistantMessageEventStream,
-	Context,
-	Model,
-	SimpleStreamOptions,
-	StreamFunction,
-	StreamOptions,
-} from "./types.ts";
-
-export type ApiStreamFunction = (
-	model: Model<Api>,
-	context: Context,
-	options?: StreamOptions,
-) => AssistantMessageEventStream;
-
-export type ApiStreamSimpleFunction = (
-	model: Model<Api>,
-	context: Context,
-	options?: SimpleStreamOptions,
-) => AssistantMessageEventStream;
-
-export interface ApiProvider<TApi extends Api = Api, TOptions extends StreamOptions = StreamOptions> {
-	api: TApi;
-	stream: StreamFunction<TApi, TOptions>;
-	streamSimple: StreamFunction<TApi, SimpleStreamOptions>;
-}
-
-interface ApiProviderInternal {
-	api: Api;
-	stream: ApiStreamFunction;
-	streamSimple: ApiStreamSimpleFunction;
-}
-
-type RegisteredApiProvider = {
-	provider: ApiProviderInternal;
-	sourceId?: string;
-};
-
-const apiProviderRegistry = new Map<string, RegisteredApiProvider>();
-
-function wrapStream<TApi extends Api, TOptions extends StreamOptions>(
-	api: TApi,
-	stream: StreamFunction<TApi, TOptions>,
-): ApiStreamFunction {
-	return (model, context, options) => {
-		if (model.api !== api) {
-			throw new Error(`Mismatched api: ${model.api} expected ${api}`);
-		}
-		return stream(model as Model<TApi>, context, options as TOptions);
-	};
-}
-
-function wrapStreamSimple<TApi extends Api>(
-	api: TApi,
-	streamSimple: StreamFunction<TApi, SimpleStreamOptions>,
-): ApiStreamSimpleFunction {
-	return (model, context, options) => {
-		if (model.api !== api) {
-			throw new Error(`Mismatched api: ${model.api} expected ${api}`);
-		}
-		return streamSimple(model as Model<TApi>, context, options);
-	};
-}
-
-export function registerApiProvider<TApi extends Api, TOptions extends StreamOptions>(
-	provider: ApiProvider<TApi, TOptions>,
-	sourceId?: string,
-): void {
-	apiProviderRegistry.set(provider.api, {
-		provider: {
-			api: provider.api,
-			stream: wrapStream(provider.api, provider.stream),
-			streamSimple: wrapStreamSimple(provider.api, provider.streamSimple),
-		},
-		sourceId,
-	});
-}
-
-export function getApiProvider(api: Api): ApiProviderInternal | undefined {
-	return apiProviderRegistry.get(api)?.provider;
-}
-
-export function getApiProviders(): ApiProviderInternal[] {
-	return Array.from(apiProviderRegistry.values(), (entry) => entry.provider);
-}
-
-export function unregisterApiProviders(sourceId: string): void {
-	for (const [api, entry] of apiProviderRegistry.entries()) {
-		if (entry.sourceId === sourceId) {
-			apiProviderRegistry.delete(api);
-		}
-	}
-}
-
-export function clearApiProviders(): void {
-	apiProviderRegistry.clear();
-}

packages/ai/src/api/anthropic-messages.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const anthropicMessagesApi = (): ProviderStreams => lazyApi(() => import("./anthropic-messages.ts"));

packages/ai/src/api/azure-openai-responses.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const azureOpenAIResponsesApi = (): ProviderStreams => lazyApi(() => import("./azure-openai-responses.ts"));

packages/ai/src/api/azure-openai-responses.ts

@@ -0,0 +1,298 @@
+import { AzureOpenAI } from "openai";
+import type { ResponseCreateParamsStreaming } from "openai/resources/responses/responses.js";
+import { clampThinkingLevel } from "../models.ts";
+import type {
+	Api,
+	AssistantMessage,
+	Context,
+	Model,
+	SimpleStreamOptions,
+	StreamFunction,
+	StreamOptions,
+} from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
+import { AssistantMessageEventStream } from "../utils/event-stream.ts";
+import { headersToRecord } from "../utils/headers.ts";
+import { getProviderEnvValue } from "../utils/provider-env.ts";
+import { clampOpenAIPromptCacheKey } from "./openai-prompt-cache.ts";
+import { convertResponsesMessages, convertResponsesTools, processResponsesStream } from "./openai-responses-shared.ts";
+import { buildBaseOptions } from "./simple-options.ts";
+
+const DEFAULT_AZURE_API_VERSION = "v1";
+const AZURE_TOOL_CALL_PROVIDERS = new Set(["openai", "openai-codex", "opencode", "azure-openai-responses"]);
+// OpenAI Responses rejects max_output_tokens below 16: https://github.com/earendil-works/pi/issues/6265
+const OPENAI_RESPONSES_MIN_OUTPUT_TOKENS = 16;
+
+function parseDeploymentNameMap(value: string | undefined): Map<string, string> {
+	const map = new Map<string, string>();
+	if (!value) return map;
+	for (const entry of value.split(",")) {
+		const trimmed = entry.trim();
+		if (!trimmed) continue;
+		const [modelId, deploymentName] = trimmed.split("=", 2);
+		if (!modelId || !deploymentName) continue;
+		map.set(modelId.trim(), deploymentName.trim());
+	}
+	return map;
+}
+
+function resolveDeploymentName(model: Model<"azure-openai-responses">, options?: AzureOpenAIResponsesOptions): string {
+	if (options?.azureDeploymentName) {
+		return options.azureDeploymentName;
+	}
+	const mappedDeployment = parseDeploymentNameMap(
+		getProviderEnvValue("AZURE_OPENAI_DEPLOYMENT_NAME_MAP", options?.env),
+	).get(model.id);
+	return mappedDeployment || model.id;
+}
+
+function formatAzureOpenAIError(error: unknown): string {
+	return formatProviderError(normalizeProviderError(error), "Azure OpenAI API error");
+}
+
+// Azure OpenAI Responses-specific options
+export interface AzureOpenAIResponsesOptions extends StreamOptions {
+	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh";
+	reasoningSummary?: "auto" | "detailed" | "concise" | null;
+	azureApiVersion?: string;
+	azureResourceName?: string;
+	azureBaseUrl?: string;
+	azureDeploymentName?: string;
+}
+
+/**
+ * Generate function for Azure OpenAI Responses API
+ */
+export const stream: StreamFunction<"azure-openai-responses", AzureOpenAIResponsesOptions> = (
+	model: Model<"azure-openai-responses">,
+	context: Context,
+	options?: AzureOpenAIResponsesOptions,
+): AssistantMessageEventStream => {
+	const stream = new AssistantMessageEventStream();
+
+	// Start async processing
+	(async () => {
+		const deploymentName = resolveDeploymentName(model, options);
+
+		const output: AssistantMessage = {
+			role: "assistant",
+			content: [],
+			api: "azure-openai-responses" as Api,
+			provider: model.provider,
+			model: model.id,
+			usage: {
+				input: 0,
+				output: 0,
+				cacheRead: 0,
+				cacheWrite: 0,
+				totalTokens: 0,
+				cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+			},
+			stopReason: "stop",
+			timestamp: Date.now(),
+		};
+
+		try {
+			// Create Azure OpenAI client
+			const apiKey = options?.apiKey;
+			if (!apiKey) {
+				throw new Error(`No API key for provider: ${model.provider}`);
+			}
+			const client = createClient(model, apiKey, options);
+			let params = buildParams(model, context, options, deploymentName);
+			const nextParams = await options?.onPayload?.(params, model);
+			if (nextParams !== undefined) {
+				params = nextParams as ResponseCreateParamsStreaming;
+			}
+			const requestOptions = {
+				...(options?.signal ? { signal: options.signal } : {}),
+				...(options?.timeoutMs !== undefined ? { timeout: options.timeoutMs } : {}),
+				maxRetries: options?.maxRetries ?? 0,
+			};
+			const { data: openaiStream, response } = await client.responses.create(params, requestOptions).withResponse();
+			await options?.onResponse?.({ status: response.status, headers: headersToRecord(response.headers) }, model);
+			stream.push({ type: "start", partial: output });
+
+			await processResponsesStream(openaiStream, output, stream, model);
+
+			if (options?.signal?.aborted) {
+				throw new Error("Request was aborted");
+			}
+
+			if (output.stopReason === "aborted" || output.stopReason === "error") {
+				throw new Error("An unknown error occurred");
+			}
+
+			stream.push({ type: "done", reason: output.stopReason, message: output });
+			stream.end();
+		} catch (error) {
+			for (const block of output.content) {
+				delete (block as { index?: number }).index;
+				// partialJson is only a streaming scratch buffer; never persist it.
+				delete (block as { partialJson?: string }).partialJson;
+			}
+			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
+			output.errorMessage = formatAzureOpenAIError(error);
+			stream.push({ type: "error", reason: output.stopReason, error: output });
+			stream.end();
+		}
+	})();
+
+	return stream;
+};
+
+export const streamSimple: StreamFunction<"azure-openai-responses", SimpleStreamOptions> = (
+	model: Model<"azure-openai-responses">,
+	context: Context,
+	options?: SimpleStreamOptions,
+): AssistantMessageEventStream => {
+	const apiKey = options?.apiKey;
+	if (!apiKey) {
+		throw new Error(`No API key for provider: ${model.provider}`);
+	}
+
+	const base = buildBaseOptions(model, context, options, apiKey);
+	const clampedReasoning = options?.reasoning ? clampThinkingLevel(model, options.reasoning) : undefined;
+	const reasoningEffort = clampedReasoning === "off" ? undefined : clampedReasoning;
+
+	return stream(model, context, {
+		...base,
+		reasoningEffort,
+	} satisfies AzureOpenAIResponsesOptions);
+};
+
+function normalizeAzureBaseUrl(baseUrl: string): string {
+	const trimmed = baseUrl.trim().replace(/\/+$/, "");
+	let url: URL;
+	try {
+		url = new URL(trimmed);
+	} catch {
+		throw new Error(`Invalid Azure OpenAI base URL: ${baseUrl}`);
+	}
+
+	const isAzureHost =
+		url.hostname.endsWith(".openai.azure.com") ||
+		url.hostname.endsWith(".cognitiveservices.azure.com") ||
+		url.hostname.endsWith(".ai.azure.com");
+	const normalizedPath = url.pathname.replace(/\/+$/, "");
+
+	// Ensure Azure hosts have /openai/v1 as base path so the AzureOpenAI SDK
+	// can append /deployments/<model>/... and ?api-version=v1 correctly.
+	if (
+		isAzureHost &&
+		(normalizedPath === "" ||
+			normalizedPath === "/" ||
+			normalizedPath === "/openai" ||
+			normalizedPath === "/openai/v1/responses")
+	) {
+		url.pathname = "/openai/v1";
+		url.search = "";
+	}
+
+	return url.toString().replace(/\/+$/, "");
+}
+
+function buildDefaultBaseUrl(resourceName: string): string {
+	return `https://${resourceName}.openai.azure.com/openai/v1`;
+}
+
+function resolveAzureConfig(
+	model: Model<"azure-openai-responses">,
+	options?: AzureOpenAIResponsesOptions,
+): { baseUrl: string; apiVersion: string } {
+	const apiVersion =
+		options?.azureApiVersion ||
+		getProviderEnvValue("AZURE_OPENAI_API_VERSION", options?.env) ||
+		DEFAULT_AZURE_API_VERSION;
+
+	const baseUrl =
+		options?.azureBaseUrl?.trim() || getProviderEnvValue("AZURE_OPENAI_BASE_URL", options?.env)?.trim() || undefined;
+	const resourceName = options?.azureResourceName || getProviderEnvValue("AZURE_OPENAI_RESOURCE_NAME", options?.env);
+
+	let resolvedBaseUrl = baseUrl;
+
+	if (!resolvedBaseUrl && resourceName) {
+		resolvedBaseUrl = buildDefaultBaseUrl(resourceName);
+	}
+
+	if (!resolvedBaseUrl && model.baseUrl) {
+		resolvedBaseUrl = model.baseUrl;
+	}
+
+	if (!resolvedBaseUrl) {
+		throw new Error(
+			"Azure OpenAI base URL is required. Set AZURE_OPENAI_BASE_URL or AZURE_OPENAI_RESOURCE_NAME, or pass azureBaseUrl, azureResourceName, or model.baseUrl.",
+		);
+	}
+
+	return {
+		baseUrl: normalizeAzureBaseUrl(resolvedBaseUrl),
+		apiVersion,
+	};
+}
+
+function createClient(model: Model<"azure-openai-responses">, apiKey: string, options?: AzureOpenAIResponsesOptions) {
+	const headers = { ...model.headers };
+
+	if (options?.headers) {
+		Object.assign(headers, options.headers);
+	}
+
+	const { baseUrl, apiVersion } = resolveAzureConfig(model, options);
+
+	return new AzureOpenAI({
+		apiKey,
+		apiVersion,
+		dangerouslyAllowBrowser: true,
+		defaultHeaders: headers,
+		baseURL: baseUrl,
+	});
+}
+
+function buildParams(
+	model: Model<"azure-openai-responses">,
+	context: Context,
+	options: AzureOpenAIResponsesOptions | undefined,
+	deploymentName: string,
+) {
+	const messages = convertResponsesMessages(model, context, AZURE_TOOL_CALL_PROVIDERS);
+
+	const params: ResponseCreateParamsStreaming = {
+		model: deploymentName,
+		input: messages,
+		stream: true,
+		prompt_cache_key: clampOpenAIPromptCacheKey(options?.sessionId),
+		store: false,
+	};
+
+	if (options?.maxTokens) {
+		params.max_output_tokens = Math.max(options.maxTokens, OPENAI_RESPONSES_MIN_OUTPUT_TOKENS);
+	}
+
+	if (options?.temperature !== undefined) {
+		params.temperature = options?.temperature;
+	}
+
+	if (context.tools && context.tools.length > 0) {
+		params.tools = convertResponsesTools(context.tools);
+	}
+
+	if (model.reasoning) {
+		if (options?.reasoningEffort || options?.reasoningSummary) {
+			const effort = options?.reasoningEffort
+				? (model.thinkingLevelMap?.[options.reasoningEffort] ?? options.reasoningEffort)
+				: "medium";
+			params.reasoning = {
+				effort: effort as NonNullable<typeof params.reasoning>["effort"],
+				summary: options?.reasoningSummary || "auto",
+			};
+			params.include = ["reasoning.encrypted_content"];
+		} else if (model.thinkingLevelMap?.off !== null) {
+			params.reasoning = {
+				effort: (model.thinkingLevelMap?.off ?? "none") as NonNullable<typeof params.reasoning>["effort"],
+			};
+		}
+	}
+
+	return params;
+}

packages/ai/src/api/bedrock-converse-stream.lazy.ts

@@ -0,0 +1,30 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+/**
+ * Loads the bedrock implementation through a variable specifier so bundlers
+ * (browser smoke, Bun compile) cannot follow the import into the Node-only
+ * AWS SDK. The `.ts`/`.js` rewrite keeps the trick working from both source
+ * and built output.
+ */
+const importNodeOnlyApi = (specifier: string): Promise<unknown> => {
+	const runtimeSpecifier = import.meta.url.endsWith(".js") ? specifier.replace(/\.ts$/, ".js") : specifier;
+	return import(runtimeSpecifier);
+};
+
+let bedrockModuleOverride: ProviderStreams | undefined;
+
+/**
+ * Overrides the dynamically imported bedrock implementation. Used by the Bun
+ * binary build, where the variable-specifier import cannot be bundled; the
+ * build registers a statically imported module instead.
+ */
+export function setBedrockProviderModule(module: ProviderStreams): void {
+	bedrockModuleOverride = module;
+}
+
+export const bedrockConverseStreamApi = (): ProviderStreams =>
+	lazyApi(
+		async () =>
+			bedrockModuleOverride ?? ((await importNodeOnlyApi("./bedrock-converse-stream.ts")) as ProviderStreams),
+	);

packages/ai/src/api/cloudflare.ts

@@ -1,6 +1,3 @@
-import type { Api, Model, ProviderEnv } from "../types.ts";
-import { getProviderEnvValue } from "../utils/provider-env.ts";
-
 /** Workers AI direct endpoint. */
 export const CLOUDFLARE_WORKERS_AI_BASE_URL =
 	"https://api.cloudflare.com/client/v4/accounts/{CLOUDFLARE_ACCOUNT_ID}/ai/v1";
@@ -16,21 +13,3 @@ export const CLOUDFLARE_AI_GATEWAY_OPENAI_BASE_URL =
 /** AI Gateway → Anthropic passthrough. */
 export const CLOUDFLARE_AI_GATEWAY_ANTHROPIC_BASE_URL =
 	"https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic";
-
-export function isCloudflareProvider(provider: string): boolean {
-	return provider === "cloudflare-workers-ai" || provider === "cloudflare-ai-gateway";
-}
-
-/** Substitute `{VAR}` placeholders in a Cloudflare baseUrl from provider env or process.env. */
-export function resolveCloudflareBaseUrl(model: Model<Api>, env?: ProviderEnv): string {
-	const url = model.baseUrl;
-	if (!url.includes("{")) return url;
-	const baseUrl = url.replace(/\{([A-Z_][A-Z0-9_]*)\}/g, (_match, name: string) => {
-		const value = getProviderEnvValue(name, env);
-		if (!value) {
-			throw new Error(`${name} is required for provider ${model.provider} but is not set.`);
-		}
-		return value;
-	});
-	return baseUrl;
-}

packages/ai/src/api/google-generative-ai.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const googleGenerativeAIApi = (): ProviderStreams => lazyApi(() => import("./google-generative-ai.ts"));

packages/ai/src/api/google-generative-ai.ts

@@ -0,0 +1,509 @@
+import {
+	type GenerateContentConfig,
+	type GenerateContentParameters,
+	GoogleGenAI,
+	type ThinkingConfig,
+} from "@google/genai";
+import { calculateCost, clampThinkingLevel } from "../models.ts";
+import type {
+	Api,
+	AssistantMessage,
+	Context,
+	Model,
+	ProviderHeaders,
+	SimpleStreamOptions,
+	StreamFunction,
+	StreamOptions,
+	TextContent,
+	ThinkingBudgets,
+	ThinkingContent,
+	ThinkingLevel,
+	ToolCall,
+} from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
+import { AssistantMessageEventStream } from "../utils/event-stream.ts";
+import { providerHeadersToRecord } from "../utils/headers.ts";
+import { sanitizeSurrogates } from "../utils/sanitize-unicode.ts";
+import type { GoogleThinkingLevel } from "./google-shared.ts";
+import {
+	convertMessages,
+	convertTools,
+	isThinkingPart,
+	mapStopReason,
+	mapToolChoice,
+	retainThoughtSignature,
+} from "./google-shared.ts";
+import { buildBaseOptions } from "./simple-options.ts";
+
+export interface GoogleOptions extends StreamOptions {
+	toolChoice?: "auto" | "none" | "any";
+	thinking?: {
+		enabled: boolean;
+		budgetTokens?: number; // -1 for dynamic, 0 to disable
+		level?: GoogleThinkingLevel;
+	};
+}
+
+// Counter for generating unique tool call IDs
+let toolCallCounter = 0;
+
+export const stream: StreamFunction<"google-generative-ai", GoogleOptions> = (
+	model: Model<"google-generative-ai">,
+	context: Context,
+	options?: GoogleOptions,
+): AssistantMessageEventStream => {
+	const stream = new AssistantMessageEventStream();
+
+	(async () => {
+		const output: AssistantMessage = {
+			role: "assistant",
+			content: [],
+			api: "google-generative-ai" as Api,
+			provider: model.provider,
+			model: model.id,
+			usage: {
+				input: 0,
+				output: 0,
+				cacheRead: 0,
+				cacheWrite: 0,
+				totalTokens: 0,
+				cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+			},
+			stopReason: "stop",
+			timestamp: Date.now(),
+		};
+
+		try {
+			const apiKey = options?.apiKey;
+			if (!apiKey) {
+				throw new Error(`No API key for provider: ${model.provider}`);
+			}
+			const client = createClient(model, apiKey, options?.headers);
+			let params = buildParams(model, context, options);
+			const nextParams = await options?.onPayload?.(params, model);
+			if (nextParams !== undefined) {
+				params = nextParams as GenerateContentParameters;
+			}
+			const googleStream = await client.models.generateContentStream(params);
+
+			stream.push({ type: "start", partial: output });
+			let currentBlock: TextContent | ThinkingContent | null = null;
+			const blocks = output.content;
+			const blockIndex = () => blocks.length - 1;
+			for await (const chunk of googleStream) {
+				// @google/genai documents GenerateContentResponse.responseId as an output-only field
+				// used to identify each response. Keep the first non-empty one from the stream.
+				output.responseId ||= chunk.responseId;
+				const candidate = chunk.candidates?.[0];
+				if (candidate?.content?.parts) {
+					for (const part of candidate.content.parts) {
+						if (part.text !== undefined) {
+							const isThinking = isThinkingPart(part);
+							if (
+								!currentBlock ||
+								(isThinking && currentBlock.type !== "thinking") ||
+								(!isThinking && currentBlock.type !== "text")
+							) {
+								if (currentBlock) {
+									if (currentBlock.type === "text") {
+										stream.push({
+											type: "text_end",
+											contentIndex: blocks.length - 1,
+											content: currentBlock.text,
+											partial: output,
+										});
+									} else {
+										stream.push({
+											type: "thinking_end",
+											contentIndex: blockIndex(),
+											content: currentBlock.thinking,
+											partial: output,
+										});
+									}
+								}
+								if (isThinking) {
+									currentBlock = { type: "thinking", thinking: "", thinkingSignature: undefined };
+									output.content.push(currentBlock);
+									stream.push({ type: "thinking_start", contentIndex: blockIndex(), partial: output });
+								} else {
+									currentBlock = { type: "text", text: "" };
+									output.content.push(currentBlock);
+									stream.push({ type: "text_start", contentIndex: blockIndex(), partial: output });
+								}
+							}
+							if (currentBlock.type === "thinking") {
+								currentBlock.thinking += part.text;
+								currentBlock.thinkingSignature = retainThoughtSignature(
+									currentBlock.thinkingSignature,
+									part.thoughtSignature,
+								);
+								stream.push({
+									type: "thinking_delta",
+									contentIndex: blockIndex(),
+									delta: part.text,
+									partial: output,
+								});
+							} else {
+								currentBlock.text += part.text;
+								currentBlock.textSignature = retainThoughtSignature(
+									currentBlock.textSignature,
+									part.thoughtSignature,
+								);
+								stream.push({
+									type: "text_delta",
+									contentIndex: blockIndex(),
+									delta: part.text,
+									partial: output,
+								});
+							}
+						}
+
+						if (part.functionCall) {
+							if (currentBlock) {
+								if (currentBlock.type === "text") {
+									stream.push({
+										type: "text_end",
+										contentIndex: blockIndex(),
+										content: currentBlock.text,
+										partial: output,
+									});
+								} else {
+									stream.push({
+										type: "thinking_end",
+										contentIndex: blockIndex(),
+										content: currentBlock.thinking,
+										partial: output,
+									});
+								}
+								currentBlock = null;
+							}
+
+							// Generate unique ID if not provided or if it's a duplicate
+							const providedId = part.functionCall.id;
+							const needsNewId =
+								!providedId || output.content.some((b) => b.type === "toolCall" && b.id === providedId);
+							const toolCallId = needsNewId
+								? `${part.functionCall.name}_${Date.now()}_${++toolCallCounter}`
+								: providedId;
+
+							const toolCall: ToolCall = {
+								type: "toolCall",
+								id: toolCallId,
+								name: part.functionCall.name || "",
+								arguments: (part.functionCall.args as Record<string, any>) ?? {},
+								...(part.thoughtSignature && { thoughtSignature: part.thoughtSignature }),
+							};
+
+							output.content.push(toolCall);
+							stream.push({ type: "toolcall_start", contentIndex: blockIndex(), partial: output });
+							stream.push({
+								type: "toolcall_delta",
+								contentIndex: blockIndex(),
+								delta: JSON.stringify(toolCall.arguments),
+								partial: output,
+							});
+							stream.push({ type: "toolcall_end", contentIndex: blockIndex(), toolCall, partial: output });
+						}
+					}
+				}
+
+				if (candidate?.finishReason) {
+					output.stopReason = mapStopReason(candidate.finishReason);
+					if (output.content.some((b) => b.type === "toolCall")) {
+						output.stopReason = "toolUse";
+					}
+				}
+
+				if (chunk.usageMetadata) {
+					output.usage = {
+						input:
+							(chunk.usageMetadata.promptTokenCount || 0) - (chunk.usageMetadata.cachedContentTokenCount || 0),
+						output:
+							(chunk.usageMetadata.candidatesTokenCount || 0) + (chunk.usageMetadata.thoughtsTokenCount || 0),
+						cacheRead: chunk.usageMetadata.cachedContentTokenCount || 0,
+						cacheWrite: 0,
+						reasoning: chunk.usageMetadata.thoughtsTokenCount || 0,
+						totalTokens: chunk.usageMetadata.totalTokenCount || 0,
+						cost: {
+							input: 0,
+							output: 0,
+							cacheRead: 0,
+							cacheWrite: 0,
+							total: 0,
+						},
+					};
+					calculateCost(model, output.usage);
+				}
+			}
+
+			if (currentBlock) {
+				if (currentBlock.type === "text") {
+					stream.push({
+						type: "text_end",
+						contentIndex: blockIndex(),
+						content: currentBlock.text,
+						partial: output,
+					});
+				} else {
+					stream.push({
+						type: "thinking_end",
+						contentIndex: blockIndex(),
+						content: currentBlock.thinking,
+						partial: output,
+					});
+				}
+			}
+
+			if (options?.signal?.aborted) {
+				throw new Error("Request was aborted");
+			}
+
+			if (output.stopReason === "aborted" || output.stopReason === "error") {
+				throw new Error("An unknown error occurred");
+			}
+
+			stream.push({ type: "done", reason: output.stopReason, message: output });
+			stream.end();
+		} catch (error) {
+			// Remove internal index property used during streaming
+			for (const block of output.content) {
+				if ("index" in block) {
+					delete (block as { index?: number }).index;
+				}
+			}
+			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
+			output.errorMessage = formatProviderError(normalizeProviderError(error));
+			stream.push({ type: "error", reason: output.stopReason, error: output });
+			stream.end();
+		}
+	})();
+
+	return stream;
+};
+
+export const streamSimple: StreamFunction<"google-generative-ai", SimpleStreamOptions> = (
+	model: Model<"google-generative-ai">,
+	context: Context,
+	options?: SimpleStreamOptions,
+): AssistantMessageEventStream => {
+	const apiKey = options?.apiKey;
+	if (!apiKey) {
+		throw new Error(`No API key for provider: ${model.provider}`);
+	}
+
+	const base = buildBaseOptions(model, context, options, apiKey);
+	if (!options?.reasoning) {
+		return stream(model, context, { ...base, thinking: { enabled: false } } satisfies GoogleOptions);
+	}
+
+	const clampedReasoning = clampThinkingLevel(model, options.reasoning);
+	const effort = (clampedReasoning === "off" ? "high" : clampedReasoning) as ClampedThinkingLevel;
+	const googleModel = model as Model<"google-generative-ai">;
+
+	if (isGemini3ProModel(googleModel) || isGemini3FlashModel(googleModel) || isGemma4Model(googleModel)) {
+		return stream(model, context, {
+			...base,
+			thinking: {
+				enabled: true,
+				level: getThinkingLevel(effort, googleModel),
+			},
+		} satisfies GoogleOptions);
+	}
+
+	return stream(model, context, {
+		...base,
+		thinking: {
+			enabled: true,
+			budgetTokens: getGoogleBudget(googleModel, effort, options.thinkingBudgets),
+		},
+	} satisfies GoogleOptions);
+};
+
+function createClient(
+	model: Model<"google-generative-ai">,
+	apiKey?: string,
+	optionsHeaders?: ProviderHeaders,
+): GoogleGenAI {
+	const httpOptions: { baseUrl?: string; apiVersion?: string; headers?: Record<string, string> } = {};
+	if (model.baseUrl) {
+		httpOptions.baseUrl = model.baseUrl;
+		httpOptions.apiVersion = ""; // baseUrl already includes version path, don't append
+	}
+	const headers = providerHeadersToRecord({ ...model.headers, ...optionsHeaders });
+	if (headers) {
+		httpOptions.headers = headers;
+	}
+
+	return new GoogleGenAI({
+		apiKey,
+		httpOptions: Object.keys(httpOptions).length > 0 ? httpOptions : undefined,
+	});
+}
+
+function buildParams(
+	model: Model<"google-generative-ai">,
+	context: Context,
+	options: GoogleOptions = {},
+): GenerateContentParameters {
+	const contents = convertMessages(model, context);
+
+	const generationConfig: GenerateContentConfig = {};
+	if (options.temperature !== undefined) {
+		generationConfig.temperature = options.temperature;
+	}
+	if (options.maxTokens !== undefined) {
+		generationConfig.maxOutputTokens = options.maxTokens;
+	}
+
+	const config: GenerateContentConfig = {
+		...(Object.keys(generationConfig).length > 0 && generationConfig),
+		...(context.systemPrompt && { systemInstruction: sanitizeSurrogates(context.systemPrompt) }),
+		...(context.tools && context.tools.length > 0 && { tools: convertTools(context.tools) }),
+	};
+
+	if (context.tools && context.tools.length > 0 && options.toolChoice) {
+		config.toolConfig = {
+			functionCallingConfig: {
+				mode: mapToolChoice(options.toolChoice),
+			},
+		};
+	} else {
+		config.toolConfig = undefined;
+	}
+
+	if (options.thinking?.enabled && model.reasoning) {
+		const thinkingConfig: ThinkingConfig = { includeThoughts: true };
+		if (options.thinking.level !== undefined) {
+			// Cast to any since our GoogleThinkingLevel mirrors Google's ThinkingLevel enum values
+			thinkingConfig.thinkingLevel = options.thinking.level as any;
+		} else if (options.thinking.budgetTokens !== undefined) {
+			thinkingConfig.thinkingBudget = options.thinking.budgetTokens;
+		}
+		config.thinkingConfig = thinkingConfig;
+	} else if (model.reasoning && options.thinking && !options.thinking.enabled) {
+		config.thinkingConfig = getDisabledThinkingConfig(model);
+	}
+
+	if (options.signal) {
+		if (options.signal.aborted) {
+			throw new Error("Request aborted");
+		}
+		config.abortSignal = options.signal;
+	}
+
+	const params: GenerateContentParameters = {
+		model: model.id,
+		contents,
+		config,
+	};
+
+	return params;
+}
+
+type ClampedThinkingLevel = Exclude<ThinkingLevel, "xhigh">;
+
+function isGemma4Model(model: Model<"google-generative-ai">): boolean {
+	return /gemma-?4/.test(model.id.toLowerCase());
+}
+
+function isGemini3ProModel(model: Model<"google-generative-ai">): boolean {
+	return /gemini-3(?:\.\d+)?-pro/.test(model.id.toLowerCase());
+}
+
+function isGemini3FlashModel(model: Model<"google-generative-ai">): boolean {
+	const id = model.id.toLowerCase();
+	return /gemini-3(?:\.\d+)?-flash/.test(id) || id === "gemini-flash-latest" || id === "gemini-flash-lite-latest";
+}
+
+function getDisabledThinkingConfig(model: Model<"google-generative-ai">): ThinkingConfig {
+	// Google docs: Gemini 3.1 Pro cannot disable thinking, and Gemini 3 Flash / Flash-Lite
+	// do not support full thinking-off either. For Gemini 3 models, use the lowest supported
+	// thinkingLevel without includeThoughts so hidden thinking remains invisible to pi.
+	if (isGemini3ProModel(model)) {
+		return { thinkingLevel: "LOW" as any };
+	}
+	if (isGemini3FlashModel(model)) {
+		return { thinkingLevel: "MINIMAL" as any };
+	}
+	if (isGemma4Model(model)) {
+		return { thinkingLevel: "MINIMAL" as any };
+	}
+
+	// Gemini 2.x supports disabling via thinkingBudget = 0.
+	return { thinkingBudget: 0 };
+}
+
+function getThinkingLevel(effort: ClampedThinkingLevel, model: Model<"google-generative-ai">): GoogleThinkingLevel {
+	if (isGemini3ProModel(model)) {
+		switch (effort) {
+			case "minimal":
+			case "low":
+				return "LOW";
+			case "medium":
+			case "high":
+				return "HIGH";
+		}
+	}
+	if (isGemma4Model(model)) {
+		switch (effort) {
+			case "minimal":
+			case "low":
+				return "MINIMAL";
+			case "medium":
+			case "high":
+				return "HIGH";
+		}
+	}
+	switch (effort) {
+		case "minimal":
+			return "MINIMAL";
+		case "low":
+			return "LOW";
+		case "medium":
+			return "MEDIUM";
+		case "high":
+			return "HIGH";
+	}
+}
+
+function getGoogleBudget(
+	model: Model<"google-generative-ai">,
+	effort: ClampedThinkingLevel,
+	customBudgets?: ThinkingBudgets,
+): number {
+	if (customBudgets?.[effort] !== undefined) {
+		return customBudgets[effort]!;
+	}
+
+	if (model.id.includes("2.5-pro")) {
+		const budgets: Record<ClampedThinkingLevel, number> = {
+			minimal: 128,
+			low: 2048,
+			medium: 8192,
+			high: 32768,
+		};
+		return budgets[effort];
+	}
+
+	if (model.id.includes("2.5-flash-lite")) {
+		const budgets: Record<ClampedThinkingLevel, number> = {
+			minimal: 512,
+			low: 2048,
+			medium: 8192,
+			high: 24576,
+		};
+		return budgets[effort];
+	}
+
+	if (model.id.includes("2.5-flash")) {
+		const budgets: Record<ClampedThinkingLevel, number> = {
+			minimal: 128,
+			low: 2048,
+			medium: 8192,
+			high: 24576,
+		};
+		return budgets[effort];
+	}
+
+	return -1;
+}

packages/ai/src/api/google-vertex.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const googleVertexApi = (): ProviderStreams => lazyApi(() => import("./google-vertex.ts"));

packages/ai/src/api/google-vertex.ts

@@ -0,0 +1,584 @@
+import {
+	type GenerateContentConfig,
+	type GenerateContentParameters,
+	GoogleGenAI,
+	type HttpOptions,
+	ResourceScope,
+	type ThinkingConfig,
+	ThinkingLevel,
+} from "@google/genai";
+import { calculateCost, clampThinkingLevel } from "../models.ts";
+import type {
+	Api,
+	AssistantMessage,
+	Context,
+	Model,
+	ThinkingLevel as PiThinkingLevel,
+	ProviderEnv,
+	ProviderHeaders,
+	SimpleStreamOptions,
+	StreamFunction,
+	StreamOptions,
+	TextContent,
+	ThinkingBudgets,
+	ThinkingContent,
+	ToolCall,
+} from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
+import { AssistantMessageEventStream } from "../utils/event-stream.ts";
+import { providerHeadersToRecord } from "../utils/headers.ts";
+import { getProviderEnvValue } from "../utils/provider-env.ts";
+import { sanitizeSurrogates } from "../utils/sanitize-unicode.ts";
+import type { GoogleThinkingLevel } from "./google-shared.ts";
+import {
+	convertMessages,
+	convertTools,
+	isThinkingPart,
+	mapStopReason,
+	mapToolChoice,
+	retainThoughtSignature,
+} from "./google-shared.ts";
+import { buildBaseOptions } from "./simple-options.ts";
+
+export interface GoogleVertexOptions extends StreamOptions {
+	toolChoice?: "auto" | "none" | "any";
+	thinking?: {
+		enabled: boolean;
+		budgetTokens?: number; // -1 for dynamic, 0 to disable
+		level?: GoogleThinkingLevel;
+	};
+	project?: string;
+	location?: string;
+}
+
+const API_VERSION = "v1";
+const GCP_VERTEX_CREDENTIALS_MARKER = "gcp-vertex-credentials";
+
+const THINKING_LEVEL_MAP: Record<GoogleThinkingLevel, ThinkingLevel> = {
+	THINKING_LEVEL_UNSPECIFIED: ThinkingLevel.THINKING_LEVEL_UNSPECIFIED,
+	MINIMAL: ThinkingLevel.MINIMAL,
+	LOW: ThinkingLevel.LOW,
+	MEDIUM: ThinkingLevel.MEDIUM,
+	HIGH: ThinkingLevel.HIGH,
+};
+
+// Counter for generating unique tool call IDs
+let toolCallCounter = 0;
+
+export const stream: StreamFunction<"google-vertex", GoogleVertexOptions> = (
+	model: Model<"google-vertex">,
+	context: Context,
+	options?: GoogleVertexOptions,
+): AssistantMessageEventStream => {
+	const stream = new AssistantMessageEventStream();
+
+	(async () => {
+		const output: AssistantMessage = {
+			role: "assistant",
+			content: [],
+			api: "google-vertex" as Api,
+			provider: model.provider,
+			model: model.id,
+			usage: {
+				input: 0,
+				output: 0,
+				cacheRead: 0,
+				cacheWrite: 0,
+				totalTokens: 0,
+				cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+			},
+			stopReason: "stop",
+			timestamp: Date.now(),
+		};
+
+		try {
+			const apiKey = resolveApiKey(options);
+			// Create the client using either a Vertex API key, if provided, or ADC with project and location
+			const client = apiKey
+				? createClientWithApiKey(model, apiKey, options?.headers)
+				: createClient(model, resolveProject(options), resolveLocation(options), options?.headers, options?.env);
+			let params = buildParams(model, context, options);
+			const nextParams = await options?.onPayload?.(params, model);
+			if (nextParams !== undefined) {
+				params = nextParams as GenerateContentParameters;
+			}
+			const googleStream = await client.models.generateContentStream(params);
+
+			stream.push({ type: "start", partial: output });
+			let currentBlock: TextContent | ThinkingContent | null = null;
+			const blocks = output.content;
+			const blockIndex = () => blocks.length - 1;
+			for await (const chunk of googleStream) {
+				// Vertex uses the same @google/genai GenerateContentResponse type as Gemini.
+				// responseId is documented there as an output-only identifier for each response.
+				output.responseId ||= chunk.responseId;
+				const candidate = chunk.candidates?.[0];
+				if (candidate?.content?.parts) {
+					for (const part of candidate.content.parts) {
+						if (part.text !== undefined) {
+							const isThinking = isThinkingPart(part);
+							if (
+								!currentBlock ||
+								(isThinking && currentBlock.type !== "thinking") ||
+								(!isThinking && currentBlock.type !== "text")
+							) {
+								if (currentBlock) {
+									if (currentBlock.type === "text") {
+										stream.push({
+											type: "text_end",
+											contentIndex: blocks.length - 1,
+											content: currentBlock.text,
+											partial: output,
+										});
+									} else {
+										stream.push({
+											type: "thinking_end",
+											contentIndex: blockIndex(),
+											content: currentBlock.thinking,
+											partial: output,
+										});
+									}
+								}
+								if (isThinking) {
+									currentBlock = { type: "thinking", thinking: "", thinkingSignature: undefined };
+									output.content.push(currentBlock);
+									stream.push({ type: "thinking_start", contentIndex: blockIndex(), partial: output });
+								} else {
+									currentBlock = { type: "text", text: "" };
+									output.content.push(currentBlock);
+									stream.push({ type: "text_start", contentIndex: blockIndex(), partial: output });
+								}
+							}
+							if (currentBlock.type === "thinking") {
+								currentBlock.thinking += part.text;
+								currentBlock.thinkingSignature = retainThoughtSignature(
+									currentBlock.thinkingSignature,
+									part.thoughtSignature,
+								);
+								stream.push({
+									type: "thinking_delta",
+									contentIndex: blockIndex(),
+									delta: part.text,
+									partial: output,
+								});
+							} else {
+								currentBlock.text += part.text;
+								currentBlock.textSignature = retainThoughtSignature(
+									currentBlock.textSignature,
+									part.thoughtSignature,
+								);
+								stream.push({
+									type: "text_delta",
+									contentIndex: blockIndex(),
+									delta: part.text,
+									partial: output,
+								});
+							}
+						}
+
+						if (part.functionCall) {
+							if (currentBlock) {
+								if (currentBlock.type === "text") {
+									stream.push({
+										type: "text_end",
+										contentIndex: blockIndex(),
+										content: currentBlock.text,
+										partial: output,
+									});
+								} else {
+									stream.push({
+										type: "thinking_end",
+										contentIndex: blockIndex(),
+										content: currentBlock.thinking,
+										partial: output,
+									});
+								}
+								currentBlock = null;
+							}
+
+							const providedId = part.functionCall.id;
+							const needsNewId =
+								!providedId || output.content.some((b) => b.type === "toolCall" && b.id === providedId);
+							const toolCallId = needsNewId
+								? `${part.functionCall.name}_${Date.now()}_${++toolCallCounter}`
+								: providedId;
+
+							const toolCall: ToolCall = {
+								type: "toolCall",
+								id: toolCallId,
+								name: part.functionCall.name || "",
+								arguments: (part.functionCall.args as Record<string, any>) ?? {},
+								...(part.thoughtSignature && { thoughtSignature: part.thoughtSignature }),
+							};
+
+							output.content.push(toolCall);
+							stream.push({ type: "toolcall_start", contentIndex: blockIndex(), partial: output });
+							stream.push({
+								type: "toolcall_delta",
+								contentIndex: blockIndex(),
+								delta: JSON.stringify(toolCall.arguments),
+								partial: output,
+							});
+							stream.push({ type: "toolcall_end", contentIndex: blockIndex(), toolCall, partial: output });
+						}
+					}
+				}
+
+				if (candidate?.finishReason) {
+					output.stopReason = mapStopReason(candidate.finishReason);
+					if (output.content.some((b) => b.type === "toolCall")) {
+						output.stopReason = "toolUse";
+					}
+				}
+
+				if (chunk.usageMetadata) {
+					output.usage = {
+						input:
+							(chunk.usageMetadata.promptTokenCount || 0) - (chunk.usageMetadata.cachedContentTokenCount || 0),
+						output:
+							(chunk.usageMetadata.candidatesTokenCount || 0) + (chunk.usageMetadata.thoughtsTokenCount || 0),
+						cacheRead: chunk.usageMetadata.cachedContentTokenCount || 0,
+						cacheWrite: 0,
+						reasoning: chunk.usageMetadata.thoughtsTokenCount || 0,
+						totalTokens: chunk.usageMetadata.totalTokenCount || 0,
+						cost: {
+							input: 0,
+							output: 0,
+							cacheRead: 0,
+							cacheWrite: 0,
+							total: 0,
+						},
+					};
+					calculateCost(model, output.usage);
+				}
+			}
+
+			if (currentBlock) {
+				if (currentBlock.type === "text") {
+					stream.push({
+						type: "text_end",
+						contentIndex: blockIndex(),
+						content: currentBlock.text,
+						partial: output,
+					});
+				} else {
+					stream.push({
+						type: "thinking_end",
+						contentIndex: blockIndex(),
+						content: currentBlock.thinking,
+						partial: output,
+					});
+				}
+			}
+
+			if (options?.signal?.aborted) {
+				throw new Error("Request was aborted");
+			}
+
+			if (output.stopReason === "aborted" || output.stopReason === "error") {
+				throw new Error("An unknown error occurred");
+			}
+
+			stream.push({ type: "done", reason: output.stopReason, message: output });
+			stream.end();
+		} catch (error) {
+			// Remove internal index property used during streaming
+			for (const block of output.content) {
+				if ("index" in block) {
+					delete (block as { index?: number }).index;
+				}
+			}
+			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
+			output.errorMessage = formatProviderError(normalizeProviderError(error));
+			stream.push({ type: "error", reason: output.stopReason, error: output });
+			stream.end();
+		}
+	})();
+
+	return stream;
+};
+
+export const streamSimple: StreamFunction<"google-vertex", SimpleStreamOptions> = (
+	model: Model<"google-vertex">,
+	context: Context,
+	options?: SimpleStreamOptions,
+): AssistantMessageEventStream => {
+	const base = buildBaseOptions(model, context, options, undefined);
+	if (!options?.reasoning) {
+		return stream(model, context, {
+			...base,
+			thinking: { enabled: false },
+		} satisfies GoogleVertexOptions);
+	}
+
+	const clampedReasoning = clampThinkingLevel(model, options.reasoning);
+	const effort = (clampedReasoning === "off" ? "high" : clampedReasoning) as ClampedThinkingLevel;
+	const geminiModel = model as unknown as Model<"google-generative-ai">;
+
+	if (isGemini3ProModel(geminiModel) || isGemini3FlashModel(geminiModel)) {
+		return stream(model, context, {
+			...base,
+			thinking: {
+				enabled: true,
+				level: getGemini3ThinkingLevel(effort, geminiModel),
+			},
+		} satisfies GoogleVertexOptions);
+	}
+
+	return stream(model, context, {
+		...base,
+		thinking: {
+			enabled: true,
+			budgetTokens: getGoogleBudget(geminiModel, effort, options.thinkingBudgets),
+		},
+	} satisfies GoogleVertexOptions);
+};
+
+function createClient(
+	model: Model<"google-vertex">,
+	project: string,
+	location: string,
+	optionsHeaders?: ProviderHeaders,
+	env?: ProviderEnv,
+): GoogleGenAI {
+	const googleAuthOptions = buildGoogleAuthOptions(env);
+	return new GoogleGenAI({
+		vertexai: true,
+		project,
+		location,
+		apiVersion: API_VERSION,
+		...(googleAuthOptions ? { googleAuthOptions } : {}),
+		httpOptions: buildHttpOptions(model, optionsHeaders),
+	});
+}
+
+function createClientWithApiKey(
+	model: Model<"google-vertex">,
+	apiKey: string,
+	optionsHeaders?: ProviderHeaders,
+): GoogleGenAI {
+	return new GoogleGenAI({
+		vertexai: true,
+		apiKey,
+		apiVersion: API_VERSION,
+		httpOptions: buildHttpOptions(model, optionsHeaders),
+	});
+}
+
+function buildHttpOptions(model: Model<"google-vertex">, optionsHeaders?: ProviderHeaders): HttpOptions | undefined {
+	const httpOptions: HttpOptions = {};
+	const baseUrl = resolveCustomBaseUrl(model.baseUrl);
+	if (baseUrl) {
+		httpOptions.baseUrl = baseUrl;
+		httpOptions.baseUrlResourceScope = ResourceScope.COLLECTION;
+		if (baseUrlIncludesApiVersion(baseUrl)) {
+			httpOptions.apiVersion = "";
+		}
+	}
+
+	const headers = providerHeadersToRecord({ ...model.headers, ...optionsHeaders });
+	if (headers) {
+		httpOptions.headers = headers;
+	}
+
+	return Object.keys(httpOptions).length > 0 ? httpOptions : undefined;
+}
+
+function resolveCustomBaseUrl(baseUrl: string): string | undefined {
+	const trimmed = baseUrl.trim();
+	if (!trimmed || trimmed.includes("{location}")) {
+		return undefined;
+	}
+	return trimmed;
+}
+
+function baseUrlIncludesApiVersion(baseUrl: string): boolean {
+	try {
+		const url = new URL(baseUrl);
+		return url.pathname.split("/").some((part) => /^v\d+(?:beta\d*)?$/.test(part));
+	} catch {
+		return /(?:^|\/)v\d+(?:beta\d*)?(?:\/|$)/.test(baseUrl);
+	}
+}
+
+function buildGoogleAuthOptions(env?: ProviderEnv): { keyFilename: string } | undefined {
+	const keyFilename = getProviderEnvValue("GOOGLE_APPLICATION_CREDENTIALS", env);
+	return keyFilename ? { keyFilename } : undefined;
+}
+
+function resolveApiKey(options?: GoogleVertexOptions): string | undefined {
+	const apiKey = options?.apiKey?.trim();
+	if (!apiKey || apiKey === GCP_VERTEX_CREDENTIALS_MARKER || isPlaceholderApiKey(apiKey)) {
+		return undefined;
+	}
+	return apiKey;
+}
+
+function isPlaceholderApiKey(apiKey: string): boolean {
+	return /^<[^>]+>$/.test(apiKey);
+}
+
+function resolveProject(options?: GoogleVertexOptions): string {
+	const project =
+		options?.project ||
+		getProviderEnvValue("GOOGLE_CLOUD_PROJECT", options?.env) ||
+		getProviderEnvValue("GCLOUD_PROJECT", options?.env);
+	if (!project) {
+		throw new Error(
+			"Vertex AI requires a project ID. Set GOOGLE_CLOUD_PROJECT/GCLOUD_PROJECT or pass project in options.",
+		);
+	}
+	return project;
+}
+
+function resolveLocation(options?: GoogleVertexOptions): string {
+	const location = options?.location || getProviderEnvValue("GOOGLE_CLOUD_LOCATION", options?.env);
+	if (!location) {
+		throw new Error("Vertex AI requires a location. Set GOOGLE_CLOUD_LOCATION or pass location in options.");
+	}
+	return location;
+}
+
+function buildParams(
+	model: Model<"google-vertex">,
+	context: Context,
+	options: GoogleVertexOptions = {},
+): GenerateContentParameters {
+	const contents = convertMessages(model, context);
+
+	const generationConfig: GenerateContentConfig = {};
+	if (options.temperature !== undefined) {
+		generationConfig.temperature = options.temperature;
+	}
+	if (options.maxTokens !== undefined) {
+		generationConfig.maxOutputTokens = options.maxTokens;
+	}
+
+	const config: GenerateContentConfig = {
+		...(Object.keys(generationConfig).length > 0 && generationConfig),
+		...(context.systemPrompt && { systemInstruction: sanitizeSurrogates(context.systemPrompt) }),
+		...(context.tools && context.tools.length > 0 && { tools: convertTools(context.tools) }),
+	};
+
+	if (context.tools && context.tools.length > 0 && options.toolChoice) {
+		config.toolConfig = {
+			functionCallingConfig: {
+				mode: mapToolChoice(options.toolChoice),
+			},
+		};
+	} else {
+		config.toolConfig = undefined;
+	}
+
+	if (options.thinking?.enabled && model.reasoning) {
+		const thinkingConfig: ThinkingConfig = { includeThoughts: true };
+		if (options.thinking.level !== undefined) {
+			thinkingConfig.thinkingLevel = THINKING_LEVEL_MAP[options.thinking.level];
+		} else if (options.thinking.budgetTokens !== undefined) {
+			thinkingConfig.thinkingBudget = options.thinking.budgetTokens;
+		}
+		config.thinkingConfig = thinkingConfig;
+	} else if (model.reasoning && options.thinking && !options.thinking.enabled) {
+		config.thinkingConfig = getDisabledThinkingConfig(model);
+	}
+
+	if (options.signal) {
+		if (options.signal.aborted) {
+			throw new Error("Request aborted");
+		}
+		config.abortSignal = options.signal;
+	}
+
+	const params: GenerateContentParameters = {
+		model: model.id,
+		contents,
+		config,
+	};
+
+	return params;
+}
+
+type ClampedThinkingLevel = Exclude<PiThinkingLevel, "xhigh">;
+
+function isGemini3ProModel(model: Model<"google-generative-ai">): boolean {
+	return /gemini-3(?:\.\d+)?-pro/.test(model.id.toLowerCase());
+}
+
+function isGemini3FlashModel(model: Model<"google-generative-ai">): boolean {
+	const id = model.id.toLowerCase();
+	return /gemini-3(?:\.\d+)?-flash/.test(id) || id === "gemini-flash-latest" || id === "gemini-flash-lite-latest";
+}
+
+function getDisabledThinkingConfig(model: Model<"google-vertex">): ThinkingConfig {
+	// Google docs: Gemini 3.1 Pro cannot disable thinking, and Gemini 3 Flash / Flash-Lite
+	// do not support full thinking-off either. For Gemini 3 models, use the lowest supported
+	// thinkingLevel without includeThoughts so hidden thinking remains invisible to pi.
+	const geminiModel = model as unknown as Model<"google-generative-ai">;
+	if (isGemini3ProModel(geminiModel)) {
+		return { thinkingLevel: ThinkingLevel.LOW };
+	}
+	if (isGemini3FlashModel(geminiModel)) {
+		return { thinkingLevel: ThinkingLevel.MINIMAL };
+	}
+
+	// Gemini 2.x supports disabling via thinkingBudget = 0.
+	return { thinkingBudget: 0 };
+}
+
+function getGemini3ThinkingLevel(
+	effort: ClampedThinkingLevel,
+	model: Model<"google-generative-ai">,
+): GoogleThinkingLevel {
+	if (isGemini3ProModel(model)) {
+		switch (effort) {
+			case "minimal":
+			case "low":
+				return "LOW";
+			case "medium":
+			case "high":
+				return "HIGH";
+		}
+	}
+	switch (effort) {
+		case "minimal":
+			return "MINIMAL";
+		case "low":
+			return "LOW";
+		case "medium":
+			return "MEDIUM";
+		case "high":
+			return "HIGH";
+	}
+}
+
+function getGoogleBudget(
+	model: Model<"google-generative-ai">,
+	effort: ClampedThinkingLevel,
+	customBudgets?: ThinkingBudgets,
+): number {
+	if (customBudgets?.[effort] !== undefined) {
+		return customBudgets[effort]!;
+	}
+
+	if (model.id.includes("2.5-pro")) {
+		const budgets: Record<ClampedThinkingLevel, number> = {
+			minimal: 128,
+			low: 2048,
+			medium: 8192,
+			high: 32768,
+		};
+		return budgets[effort];
+	}
+
+	if (model.id.includes("2.5-flash")) {
+		const budgets: Record<ClampedThinkingLevel, number> = {
+			minimal: 128,
+			low: 2048,
+			medium: 8192,
+			high: 24576,
+		};
+		return budgets[effort];
+	}
+
+	return -1;
+}

packages/ai/src/api/lazy.ts

@@ -0,0 +1,70 @@
+import type { Api, AssistantMessage, AssistantMessageEvent, Model, ProviderStreams } from "../types.ts";
+import { AssistantMessageEventStream } from "../utils/event-stream.ts";
+
+function createSetupErrorMessage(model: Model<Api>, error: unknown): AssistantMessage {
+	return {
+		role: "assistant",
+		content: [],
+		api: model.api,
+		provider: model.provider,
+		model: model.id,
+		usage: {
+			input: 0,
+			output: 0,
+			cacheRead: 0,
+			cacheWrite: 0,
+			totalTokens: 0,
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+		},
+		stopReason: "error",
+		errorMessage: error instanceof Error ? error.message : String(error),
+		timestamp: Date.now(),
+	};
+}
+
+function forwardStream(target: AssistantMessageEventStream, source: AsyncIterable<AssistantMessageEvent>): void {
+	(async () => {
+		for await (const event of source) {
+			target.push(event);
+		}
+		target.end();
+	})();
+}
+
+/**
+ * Returns a stream synchronously while running async setup (auth resolution,
+ * lazy module loading) behind it. Setup failures terminate the stream with an
+ * error event.
+ */
+export function lazyStream(
+	model: Model<Api>,
+	setup: () => Promise<AsyncIterable<AssistantMessageEvent>>,
+): AssistantMessageEventStream {
+	const outer = new AssistantMessageEventStream();
+
+	setup()
+		.then((inner) => {
+			forwardStream(outer, inner);
+		})
+		.catch((error) => {
+			const message = createSetupErrorMessage(model, error);
+			outer.push({ type: "error", reason: "error", error: message });
+			outer.end(message);
+		});
+
+	return outer;
+}
+
+/**
+ * Wraps a dynamically imported API implementation module as `ProviderStreams`.
+ * The module loads on first stream call; the host's import cache deduplicates
+ * loads. Load failures terminate the returned stream with an error event.
+ */
+export function lazyApi(load: () => Promise<ProviderStreams>): ProviderStreams {
+	return {
+		stream: (model, context, options) =>
+			lazyStream(model, async () => (await load()).stream(model, context, options)),
+		streamSimple: (model, context, options) =>
+			lazyStream(model, async () => (await load()).streamSimple(model, context, options)),
+	};
+}

packages/ai/src/api/mistral-conversations.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const mistralConversationsApi = (): ProviderStreams => lazyApi(() => import("./mistral-conversations.ts"));

packages/ai/src/api/mistral-conversations.ts

@@ -0,0 +1,664 @@
+import { Mistral } from "@mistralai/mistralai";
+import type {
+	ChatCompletionStreamRequest,
+	ChatCompletionStreamRequestMessage,
+	CompletionEvent,
+	ContentChunk,
+	FunctionTool,
+} from "@mistralai/mistralai/models/components";
+import { calculateCost, clampThinkingLevel } from "../models.ts";
+import type {
+	AssistantMessage,
+	Context,
+	Message,
+	Model,
+	SimpleStreamOptions,
+	StopReason,
+	StreamFunction,
+	StreamOptions,
+	TextContent,
+	ThinkingContent,
+	Tool,
+	ToolCall,
+} from "../types.ts";
+import { AssistantMessageEventStream } from "../utils/event-stream.ts";
+import { shortHash } from "../utils/hash.ts";
+import { parseStreamingJson } from "../utils/json-parse.ts";
+import { sanitizeSurrogates } from "../utils/sanitize-unicode.ts";
+import { buildBaseOptions } from "./simple-options.ts";
+import { transformMessages } from "./transform-messages.ts";
+
+const MISTRAL_TOOL_CALL_ID_LENGTH = 9;
+const MAX_MISTRAL_ERROR_BODY_CHARS = 4000;
+
+/**
+ * Provider-specific options for the Mistral API.
+ */
+type MistralReasoningEffort = "none" | "high";
+
+export interface MistralOptions extends StreamOptions {
+	toolChoice?: "auto" | "none" | "any" | "required" | { type: "function"; function: { name: string } };
+	promptMode?: "reasoning";
+	reasoningEffort?: MistralReasoningEffort;
+}
+
+/**
+ * Stream responses from Mistral using `chat.stream`.
+ */
+export const stream: StreamFunction<"mistral-conversations", MistralOptions> = (
+	model: Model<"mistral-conversations">,
+	context: Context,
+	options?: MistralOptions,
+): AssistantMessageEventStream => {
+	const stream = new AssistantMessageEventStream();
+
+	(async () => {
+		const output = createOutput(model);
+
+		try {
+			const apiKey = options?.apiKey;
+			if (!apiKey) {
+				throw new Error(`No API key for provider: ${model.provider}`);
+			}
+
+			// Intentionally per-request: avoids shared SDK mutable state across concurrent consumers.
+			const mistral = new Mistral({
+				apiKey,
+				serverURL: model.baseUrl,
+			});
+
+			const normalizeMistralToolCallId = createMistralToolCallIdNormalizer();
+			const transformedMessages = transformMessages(context.messages, model, (id) => normalizeMistralToolCallId(id));
+
+			let payload = buildChatPayload(model, context, transformedMessages, options);
+			const nextPayload = await options?.onPayload?.(payload, model);
+			if (nextPayload !== undefined) {
+				payload = nextPayload as ChatCompletionStreamRequest;
+			}
+			const mistralStream = await mistral.chat.stream(payload, buildRequestOptions(model, options));
+			stream.push({ type: "start", partial: output });
+			await consumeChatStream(model, output, stream, mistralStream);
+
+			if (options?.signal?.aborted) {
+				throw new Error("Request was aborted");
+			}
+
+			if (output.stopReason === "aborted" || output.stopReason === "error") {
+				throw new Error("An unknown error occurred");
+			}
+
+			stream.push({ type: "done", reason: output.stopReason, message: output });
+			stream.end();
+		} catch (error) {
+			for (const block of output.content) {
+				// partialArgs is only a streaming scratch buffer; never persist it.
+				delete (block as { partialArgs?: string }).partialArgs;
+			}
+			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
+			output.errorMessage = formatMistralError(error);
+			stream.push({ type: "error", reason: output.stopReason, error: output });
+			stream.end();
+		}
+	})();
+
+	return stream;
+};
+
+/**
+ * Maps provider-agnostic `SimpleStreamOptions` to Mistral options.
+ */
+export const streamSimple: StreamFunction<"mistral-conversations", SimpleStreamOptions> = (
+	model: Model<"mistral-conversations">,
+	context: Context,
+	options?: SimpleStreamOptions,
+): AssistantMessageEventStream => {
+	const apiKey = options?.apiKey;
+	if (!apiKey) {
+		throw new Error(`No API key for provider: ${model.provider}`);
+	}
+
+	const base = buildBaseOptions(model, context, options, apiKey);
+	const clampedReasoning = options?.reasoning ? clampThinkingLevel(model, options.reasoning) : undefined;
+	const reasoning = clampedReasoning === "off" ? undefined : clampedReasoning;
+	const shouldUseReasoning = model.reasoning && reasoning !== undefined;
+
+	return stream(model, context, {
+		...base,
+		promptMode: shouldUseReasoning && usesPromptModeReasoning(model) ? "reasoning" : undefined,
+		reasoningEffort:
+			shouldUseReasoning && usesReasoningEffort(model) ? mapReasoningEffort(model, reasoning) : undefined,
+	} satisfies MistralOptions);
+};
+
+function createOutput(model: Model<"mistral-conversations">): AssistantMessage {
+	return {
+		role: "assistant",
+		content: [],
+		api: model.api,
+		provider: model.provider,
+		model: model.id,
+		usage: {
+			input: 0,
+			output: 0,
+			cacheRead: 0,
+			cacheWrite: 0,
+			totalTokens: 0,
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+		},
+		stopReason: "stop",
+		timestamp: Date.now(),
+	};
+}
+
+function createMistralToolCallIdNormalizer(): (id: string) => string {
+	const idMap = new Map<string, string>();
+	const reverseMap = new Map<string, string>();
+
+	return (id: string): string => {
+		const existing = idMap.get(id);
+		if (existing) return existing;
+
+		let attempt = 0;
+		while (true) {
+			const candidate = deriveMistralToolCallId(id, attempt);
+			const owner = reverseMap.get(candidate);
+			if (!owner || owner === id) {
+				idMap.set(id, candidate);
+				reverseMap.set(candidate, id);
+				return candidate;
+			}
+			attempt++;
+		}
+	};
+}
+
+function deriveMistralToolCallId(id: string, attempt: number): string {
+	const normalized = id.replace(/[^a-zA-Z0-9]/g, "");
+	if (attempt === 0 && normalized.length === MISTRAL_TOOL_CALL_ID_LENGTH) return normalized;
+	const seedBase = normalized || id;
+	const seed = attempt === 0 ? seedBase : `${seedBase}:${attempt}`;
+	return shortHash(seed)
+		.replace(/[^a-zA-Z0-9]/g, "")
+		.slice(0, MISTRAL_TOOL_CALL_ID_LENGTH);
+}
+
+function formatMistralError(error: unknown): string {
+	if (error instanceof Error) {
+		const sdkError = error as Error & { statusCode?: unknown; body?: unknown };
+		const statusCode = typeof sdkError.statusCode === "number" ? sdkError.statusCode : undefined;
+		const bodyText = typeof sdkError.body === "string" ? sdkError.body.trim() : undefined;
+		if (statusCode !== undefined && bodyText) {
+			return `Mistral API error (${statusCode}): ${truncateErrorText(bodyText, MAX_MISTRAL_ERROR_BODY_CHARS)}`;
+		}
+		if (statusCode !== undefined) return `Mistral API error (${statusCode}): ${error.message}`;
+		return error.message;
+	}
+	return safeJsonStringify(error);
+}
+
+function truncateErrorText(text: string, maxChars: number): string {
+	if (text.length <= maxChars) return text;
+	return `${text.slice(0, maxChars)}... [truncated ${text.length - maxChars} chars]`;
+}
+
+function safeJsonStringify(value: unknown): string {
+	try {
+		const serialized = JSON.stringify(value);
+		return serialized === undefined ? String(value) : serialized;
+	} catch {
+		return String(value);
+	}
+}
+
+function buildRequestOptions(model: Model<"mistral-conversations">, options?: MistralOptions) {
+	const requestOptions: {
+		signal?: AbortSignal;
+		retries: { strategy: "none" };
+		headers?: Record<string, string>;
+	} = {
+		retries: { strategy: "none" },
+	};
+	if (options?.signal) requestOptions.signal = options.signal;
+
+	const headers: Record<string, string> = {};
+	if (model.headers) Object.assign(headers, model.headers);
+	if (options?.headers) Object.assign(headers, options.headers);
+
+	// Mistral infrastructure uses `x-affinity` for KV-cache reuse (prefix caching).
+	// Respect explicit caller-provided header values.
+	if (shouldUsePromptCaching(options) && !headers["x-affinity"]) {
+		headers["x-affinity"] = options.sessionId;
+	}
+
+	if (Object.keys(headers).length > 0) {
+		requestOptions.headers = headers;
+	}
+
+	return requestOptions;
+}
+
+function buildChatPayload(
+	model: Model<"mistral-conversations">,
+	context: Context,
+	messages: Message[],
+	options?: MistralOptions,
+): ChatCompletionStreamRequest {
+	const payload: ChatCompletionStreamRequest = {
+		model: model.id,
+		stream: true,
+		messages: toChatMessages(messages, model.input.includes("image")),
+	};
+
+	if (context.tools?.length) payload.tools = toFunctionTools(context.tools);
+	if (options?.temperature !== undefined) payload.temperature = options.temperature;
+	if (options?.maxTokens !== undefined) payload.maxTokens = options.maxTokens;
+	if (options?.toolChoice) payload.toolChoice = mapToolChoice(options.toolChoice);
+	if (options?.promptMode) payload.promptMode = options.promptMode;
+	if (options?.reasoningEffort) payload.reasoningEffort = options.reasoningEffort;
+	if (shouldUsePromptCaching(options)) payload.promptCacheKey = options.sessionId;
+
+	if (context.systemPrompt) {
+		payload.messages.unshift({
+			role: "system",
+			content: sanitizeSurrogates(context.systemPrompt),
+		});
+	}
+
+	return payload;
+}
+
+function shouldUsePromptCaching(options?: MistralOptions): options is MistralOptions & { sessionId: string } {
+	return options?.cacheRetention !== "none" && !!options?.sessionId;
+}
+
+function getMistralCachedPromptTokens(usage: unknown, promptTokens: number): number {
+	const rawUsage = usage as {
+		promptTokensDetails?: { cachedTokens?: unknown } | null;
+		prompt_tokens_details?: { cached_tokens?: unknown } | null;
+		promptTokenDetails?: { cachedTokens?: unknown } | null;
+		prompt_token_details?: { cached_tokens?: unknown } | null;
+		numCachedTokens?: unknown;
+		num_cached_tokens?: unknown;
+	};
+	const rawCachedTokens =
+		rawUsage.promptTokensDetails?.cachedTokens ??
+		rawUsage.prompt_tokens_details?.cached_tokens ??
+		rawUsage.promptTokenDetails?.cachedTokens ??
+		rawUsage.prompt_token_details?.cached_tokens ??
+		rawUsage.numCachedTokens ??
+		rawUsage.num_cached_tokens ??
+		0;
+	const cachedTokens = typeof rawCachedTokens === "number" && Number.isFinite(rawCachedTokens) ? rawCachedTokens : 0;
+	return Math.min(promptTokens, Math.max(0, cachedTokens));
+}
+
+async function consumeChatStream(
+	model: Model<"mistral-conversations">,
+	output: AssistantMessage,
+	stream: AssistantMessageEventStream,
+	mistralStream: AsyncIterable<CompletionEvent>,
+): Promise<void> {
+	let currentBlock: TextContent | ThinkingContent | null = null;
+	const blocks = output.content;
+	const blockIndex = () => blocks.length - 1;
+	const toolBlocksByKey = new Map<string, number>();
+
+	const finishCurrentBlock = (block?: typeof currentBlock) => {
+		if (!block) return;
+		if (block.type === "text") {
+			stream.push({
+				type: "text_end",
+				contentIndex: blockIndex(),
+				content: block.text,
+				partial: output,
+			});
+			return;
+		}
+		if (block.type === "thinking") {
+			stream.push({
+				type: "thinking_end",
+				contentIndex: blockIndex(),
+				content: block.thinking,
+				partial: output,
+			});
+		}
+	};
+
+	for await (const event of mistralStream) {
+		const chunk = event.data;
+		// Mistral's streamed CompletionChunk carries an id field. Keep the first non-empty one,
+		// mirroring how OpenAI-style streaming exposes a stable response identifier per stream.
+		output.responseId ||= chunk.id;
+
+		if (chunk.usage) {
+			const promptTokens = chunk.usage.promptTokens || 0;
+			const cachedPromptTokens = getMistralCachedPromptTokens(chunk.usage, promptTokens);
+
+			output.usage.input = Math.max(0, promptTokens - cachedPromptTokens);
+			output.usage.output = chunk.usage.completionTokens || 0;
+			output.usage.cacheRead = cachedPromptTokens;
+			output.usage.cacheWrite = 0;
+			output.usage.totalTokens =
+				chunk.usage.totalTokens ||
+				output.usage.input + output.usage.output + output.usage.cacheRead + output.usage.cacheWrite;
+			calculateCost(model, output.usage);
+		}
+
+		const choice = chunk.choices[0];
+		if (!choice) continue;
+
+		if (choice.finishReason) {
+			output.stopReason = mapChatStopReason(choice.finishReason);
+		}
+
+		const delta = choice.delta;
+		if (delta.content !== null && delta.content !== undefined) {
+			const contentItems = typeof delta.content === "string" ? [delta.content] : delta.content;
+			for (const item of contentItems) {
+				if (typeof item === "string") {
+					const textDelta = sanitizeSurrogates(item);
+					if (!currentBlock || currentBlock.type !== "text") {
+						finishCurrentBlock(currentBlock);
+						currentBlock = { type: "text", text: "" };
+						output.content.push(currentBlock);
+						stream.push({ type: "text_start", contentIndex: blockIndex(), partial: output });
+					}
+					currentBlock.text += textDelta;
+					stream.push({
+						type: "text_delta",
+						contentIndex: blockIndex(),
+						delta: textDelta,
+						partial: output,
+					});
+					continue;
+				}
+
+				if (item.type === "thinking") {
+					const deltaText = item.thinking
+						.map((part) => ("text" in part ? part.text : ""))
+						.filter((text) => text.length > 0)
+						.join("");
+					const thinkingDelta = sanitizeSurrogates(deltaText);
+					if (!thinkingDelta) continue;
+					if (!currentBlock || currentBlock.type !== "thinking") {
+						finishCurrentBlock(currentBlock);
+						currentBlock = { type: "thinking", thinking: "" };
+						output.content.push(currentBlock);
+						stream.push({ type: "thinking_start", contentIndex: blockIndex(), partial: output });
+					}
+					currentBlock.thinking += thinkingDelta;
+					stream.push({
+						type: "thinking_delta",
+						contentIndex: blockIndex(),
+						delta: thinkingDelta,
+						partial: output,
+					});
+					continue;
+				}
+
+				if (item.type === "text") {
+					const textDelta = sanitizeSurrogates(item.text);
+					if (!currentBlock || currentBlock.type !== "text") {
+						finishCurrentBlock(currentBlock);
+						currentBlock = { type: "text", text: "" };
+						output.content.push(currentBlock);
+						stream.push({ type: "text_start", contentIndex: blockIndex(), partial: output });
+					}
+					currentBlock.text += textDelta;
+					stream.push({
+						type: "text_delta",
+						contentIndex: blockIndex(),
+						delta: textDelta,
+						partial: output,
+					});
+				}
+			}
+		}
+
+		const toolCalls = delta.toolCalls || [];
+		for (const toolCall of toolCalls) {
+			if (currentBlock) {
+				finishCurrentBlock(currentBlock);
+				currentBlock = null;
+			}
+			const callId =
+				toolCall.id && toolCall.id !== "null"
+					? toolCall.id
+					: deriveMistralToolCallId(`toolcall:${toolCall.index ?? 0}`, 0);
+			const key = `${callId}:${toolCall.index || 0}`;
+			const existingIndex = toolBlocksByKey.get(key);
+			let block: (ToolCall & { partialArgs?: string }) | undefined;
+
+			if (existingIndex !== undefined) {
+				const existing = output.content[existingIndex];
+				if (existing?.type === "toolCall") {
+					block = existing as ToolCall & { partialArgs?: string };
+				}
+			}
+
+			if (!block) {
+				block = {
+					type: "toolCall",
+					id: callId,
+					name: toolCall.function.name,
+					arguments: {},
+					partialArgs: "",
+				};
+				output.content.push(block);
+				toolBlocksByKey.set(key, output.content.length - 1);
+				stream.push({ type: "toolcall_start", contentIndex: output.content.length - 1, partial: output });
+			}
+
+			const argsDelta =
+				typeof toolCall.function.arguments === "string"
+					? toolCall.function.arguments
+					: JSON.stringify(toolCall.function.arguments || {});
+			block.partialArgs = (block.partialArgs || "") + argsDelta;
+			block.arguments = parseStreamingJson<Record<string, unknown>>(block.partialArgs);
+			stream.push({
+				type: "toolcall_delta",
+				contentIndex: toolBlocksByKey.get(key)!,
+				delta: argsDelta,
+				partial: output,
+			});
+		}
+	}
+
+	finishCurrentBlock(currentBlock);
+	for (const index of toolBlocksByKey.values()) {
+		const block = output.content[index];
+		if (block.type !== "toolCall") continue;
+		const toolBlock = block as ToolCall & { partialArgs?: string };
+		toolBlock.arguments = parseStreamingJson<Record<string, unknown>>(toolBlock.partialArgs);
+		// Finalize in-place and strip the scratch buffer so replay only
+		// carries parsed arguments.
+		delete toolBlock.partialArgs;
+		stream.push({
+			type: "toolcall_end",
+			contentIndex: index,
+			toolCall: toolBlock,
+			partial: output,
+		});
+	}
+}
+
+function toFunctionTools(tools: Tool[]): Array<FunctionTool & { type: "function" }> {
+	return tools.map((tool) => ({
+		type: "function",
+		function: {
+			name: tool.name,
+			description: tool.description,
+			parameters: stripSymbolKeys(tool.parameters) as Record<string, unknown>,
+			strict: false,
+		},
+	}));
+}
+
+function stripSymbolKeys(value: unknown): unknown {
+	if (Array.isArray(value)) {
+		return value.map((item) => stripSymbolKeys(item));
+	}
+
+	if (value && typeof value === "object") {
+		const result: Record<string, unknown> = {};
+		for (const [key, entry] of Object.entries(value)) {
+			result[key] = stripSymbolKeys(entry);
+		}
+		return result;
+	}
+
+	return value;
+}
+
+function toChatMessages(messages: Message[], supportsImages: boolean): ChatCompletionStreamRequestMessage[] {
+	const result: ChatCompletionStreamRequestMessage[] = [];
+
+	for (const msg of messages) {
+		if (msg.role === "user") {
+			if (typeof msg.content === "string") {
+				result.push({ role: "user", content: sanitizeSurrogates(msg.content) });
+				continue;
+			}
+			const hadImages = msg.content.some((item) => item.type === "image");
+			const content: ContentChunk[] = msg.content
+				.filter((item) => item.type === "text" || supportsImages)
+				.map((item) => {
+					if (item.type === "text") return { type: "text", text: sanitizeSurrogates(item.text) };
+					return { type: "image_url", imageUrl: `data:${item.mimeType};base64,${item.data}` };
+				});
+			if (content.length > 0) {
+				result.push({ role: "user", content });
+				continue;
+			}
+			if (hadImages && !supportsImages) {
+				result.push({ role: "user", content: "(image omitted: model does not support images)" });
+			}
+			continue;
+		}
+
+		if (msg.role === "assistant") {
+			const contentParts: ContentChunk[] = [];
+			const toolCalls: Array<{ id: string; type: "function"; function: { name: string; arguments: string } }> = [];
+
+			for (const block of msg.content) {
+				if (block.type === "text") {
+					if (block.text.trim().length > 0) {
+						contentParts.push({ type: "text", text: sanitizeSurrogates(block.text) });
+					}
+					continue;
+				}
+				if (block.type === "thinking") {
+					if (block.thinking.trim().length > 0) {
+						contentParts.push({
+							type: "thinking",
+							thinking: [{ type: "text", text: sanitizeSurrogates(block.thinking) }],
+						});
+					}
+					continue;
+				}
+				toolCalls.push({
+					id: block.id,
+					type: "function",
+					function: { name: block.name, arguments: JSON.stringify(block.arguments || {}) },
+				});
+			}
+
+			const assistantMessage: ChatCompletionStreamRequestMessage = { role: "assistant" };
+			if (contentParts.length > 0) assistantMessage.content = contentParts;
+			if (toolCalls.length > 0) assistantMessage.toolCalls = toolCalls;
+			if (contentParts.length > 0 || toolCalls.length > 0) result.push(assistantMessage);
+			continue;
+		}
+
+		const toolContent: ContentChunk[] = [];
+		const textResult = msg.content
+			.filter((part) => part.type === "text")
+			.map((part) => (part.type === "text" ? sanitizeSurrogates(part.text) : ""))
+			.join("\n");
+		const hasImages = msg.content.some((part) => part.type === "image");
+		const toolText = buildToolResultText(textResult, hasImages, supportsImages, msg.isError);
+		toolContent.push({ type: "text", text: toolText });
+		for (const part of msg.content) {
+			if (!supportsImages) continue;
+			if (part.type !== "image") continue;
+			toolContent.push({
+				type: "image_url",
+				imageUrl: `data:${part.mimeType};base64,${part.data}`,
+			});
+		}
+		result.push({
+			role: "tool",
+			toolCallId: msg.toolCallId,
+			name: msg.toolName,
+			content: toolContent,
+		});
+	}
+
+	return result;
+}
+
+function buildToolResultText(text: string, hasImages: boolean, supportsImages: boolean, isError: boolean): string {
+	const trimmed = text.trim();
+	const errorPrefix = isError ? "[tool error] " : "";
+
+	if (trimmed.length > 0) {
+		const imageSuffix = hasImages && !supportsImages ? "\n[tool image omitted: model does not support images]" : "";
+		return `${errorPrefix}${trimmed}${imageSuffix}`;
+	}
+
+	if (hasImages) {
+		if (supportsImages) {
+			return isError ? "[tool error] (see attached image)" : "(see attached image)";
+		}
+		return isError
+			? "[tool error] (image omitted: model does not support images)"
+			: "(image omitted: model does not support images)";
+	}
+
+	return isError ? "[tool error] (no tool output)" : "(no tool output)";
+}
+
+function usesReasoningEffort(model: Model<"mistral-conversations">): boolean {
+	return model.id === "mistral-small-2603" || model.id === "mistral-small-latest" || model.id === "mistral-medium-3.5";
+}
+
+function usesPromptModeReasoning(model: Model<"mistral-conversations">): boolean {
+	return model.reasoning && !usesReasoningEffort(model);
+}
+
+function mapReasoningEffort(
+	model: Model<"mistral-conversations">,
+	level: Exclude<SimpleStreamOptions["reasoning"], undefined>,
+): MistralReasoningEffort {
+	return (model.thinkingLevelMap?.[level] ?? "high") as MistralReasoningEffort;
+}
+
+function mapToolChoice(
+	choice: MistralOptions["toolChoice"],
+): "auto" | "none" | "any" | "required" | { type: "function"; function: { name: string } } | undefined {
+	if (!choice) return undefined;
+	if (choice === "auto" || choice === "none" || choice === "any" || choice === "required") {
+		return choice as any;
+	}
+	return {
+		type: "function",
+		function: { name: choice.function.name },
+	};
+}
+
+function mapChatStopReason(reason: string | null): StopReason {
+	if (reason === null) return "stop";
+	switch (reason) {
+		case "stop":
+			return "stop";
+		case "length":
+		case "model_length":
+			return "length";
+		case "tool_calls":
+			return "toolUse";
+		case "error":
+			return "error";
+		default:
+			return "stop";
+	}
+}

packages/ai/src/api/openai-codex-responses.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const openAICodexResponsesApi = (): ProviderStreams => lazyApi(() => import("./openai-codex-responses.ts"));

packages/ai/src/api/openai-codex-responses.ts

@@ -1,4 +1,5 @@
 import type * as NodeOs from "node:os";
+import type * as NodeZlib from "node:zlib";
 import type {
 	Tool as OpenAITool,
 	ResponseCreateParamsStreaming,
@@ -6,21 +7,20 @@ import type {
 	ResponseStreamEvent,
 } from "openai/resources/responses/responses.js";
 
-// NEVER convert to top-level runtime imports - breaks browser/Vite builds
-let _os: typeof NodeOs | null = null;
+type ProcessWithOsBuiltinModule = typeof process & {
+	getBuiltinModule?: (id: "node:os") => typeof NodeOs;
+};
 
-type DynamicImport = (specifier: string) => Promise<unknown>;
-
-const dynamicImport: DynamicImport = (specifier) => import(specifier);
-const NODE_OS_SPECIFIER = "node:" + "os";
-
-if (typeof process !== "undefined" && (process.versions?.node || process.versions?.bun)) {
-	dynamicImport(NODE_OS_SPECIFIER).then((m) => {
-		_os = m as typeof NodeOs;
-	});
+function loadNodeOs(): typeof NodeOs | null {
+	if (typeof process === "undefined" || !(process.versions?.node || process.versions?.bun)) {
+		return null;
+	}
+	return (process as ProcessWithOsBuiltinModule).getBuiltinModule?.("node:os") ?? null;
 }
 
-import { registerApiProvider } from "../api-registry.ts";
+// NEVER convert to top-level runtime imports - breaks browser/Vite builds
+const _os: typeof NodeOs | null = loadNodeOs();
+
 import { clampThinkingLevel } from "../models.ts";
 import { registerSessionResourceCleanup } from "../session-resources.ts";
 import type {
@@ -29,6 +29,7 @@ import type {
 	Context,
 	Model,
 	ProviderEnv,
+	ProviderHeaders,
 	SimpleStreamOptions,
 	StreamFunction,
 	StreamOptions,
@@ -40,6 +41,7 @@ import {
 	createAssistantMessageDiagnostic,
 	formatThrownValue,
 } from "../utils/diagnostics.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
 import { AssistantMessageEventStream } from "../utils/event-stream.ts";
 import { headersToRecord } from "../utils/headers.ts";
 import { resolveHttpProxyUrlForTarget } from "../utils/node-http-proxy.ts";
@@ -56,12 +58,13 @@ const JWT_CLAIM_PATH = "https://api.openai.com/auth" as const;
 const DEFAULT_MAX_RETRIES = 0;
 const BASE_DELAY_MS = 1000;
 const DEFAULT_MAX_RETRY_DELAY_MS = 60_000;
-// Keep a bounded pre-header timeout so zero-event Codex SSE stalls fail instead of
-// leaving callers stuck on "Working..." indefinitely. See #4945.
-const DEFAULT_SSE_HEADER_TIMEOUT_MS = 20_000;
 const DEFAULT_WEBSOCKET_CONNECT_TIMEOUT_MS = 15_000;
+// The Codex backend accepts zstd-compressed request bodies on the SSE responses
+// endpoint (the same endpoint the official Codex client compresses against).
+const REQUEST_COMPRESSION_ZSTD_LEVEL = 3;
 const CODEX_TOOL_CALL_PROVIDERS = new Set(["openai", "openai-codex", "opencode"]);
 const WEBSOCKET_MESSAGE_TOO_BIG_CLOSE_CODE = 1009;
+const WEBSOCKET_CONNECTION_LIMIT_REACHED_CODE = "websocket_connection_limit_reached";
 
 const CODEX_RESPONSE_STATUSES = new Set<CodexResponseStatus>([
 	"completed",
@@ -178,25 +181,44 @@ function normalizeTimeoutMs(value: number | undefined): number | undefined {
 	return Math.floor(value);
 }
 
-function createSSEHeaderTimeout(): { signal: AbortSignal; clear: () => void; error: () => Error | undefined } {
-	const controller = new AbortController();
-	let error: Error | undefined;
-	const timeout = setTimeout(() => {
-		error = new Error(`Codex SSE response headers timed out after ${DEFAULT_SSE_HEADER_TIMEOUT_MS}ms`);
-		controller.abort(error);
-	}, DEFAULT_SSE_HEADER_TIMEOUT_MS);
-	return {
-		signal: controller.signal,
-		clear: () => clearTimeout(timeout),
-		error: () => error,
-	};
+// ============================================================================
+// Request Compression
+// ============================================================================
+
+type ProcessWithBuiltinModule = typeof process & {
+	getBuiltinModule?: (id: "node:zlib") => typeof NodeZlib;
+};
+
+function loadNodeZlib(): typeof NodeZlib | null {
+	if (typeof process === "undefined" || !(process.versions?.node || process.versions?.bun)) {
+		return null;
+	}
+	return (process as ProcessWithBuiltinModule).getBuiltinModule?.("node:zlib") ?? null;
+}
+
+// Returns the zstd-compressed body bytes, or null when compression is
+// unavailable (browser/Vite builds). Callers fall back to sending the
+// uncompressed JSON when this returns null.
+function compressRequestBodyZstd(bodyJson: string): Uint8Array | null {
+	const zlib = loadNodeZlib();
+	if (!zlib || typeof zlib.zstdCompressSync !== "function") {
+		return null;
+	}
+	try {
+		const compressed = zlib.zstdCompressSync(bodyJson, {
+			params: { [zlib.constants.ZSTD_c_compressionLevel]: REQUEST_COMPRESSION_ZSTD_LEVEL },
+		});
+		return new Uint8Array(compressed.buffer, compressed.byteOffset, compressed.byteLength);
+	} catch {
+		return null;
+	}
 }
 
 // ============================================================================
 // Main Stream Function
 // ============================================================================
 
-export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses", OpenAICodexResponsesOptions> = (
+export const stream: StreamFunction<"openai-codex-responses", OpenAICodexResponsesOptions> = (
 	model: Model<"openai-codex-responses">,
 	context: Context,
 	options?: OpenAICodexResponsesOptions,
@@ -244,7 +266,7 @@ export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses"
 				websocketRequestId,
 			);
 			const bodyJson = JSON.stringify(body);
-			const idleTimeoutMs = normalizeTimeoutMs(options?.timeoutMs);
+			const httpTimeoutMs = normalizeTimeoutMs(options?.timeoutMs);
 			const websocketConnectTimeoutMs = normalizeTimeoutMs(options?.websocketConnectTimeoutMs);
 			const transport = options?.transport || "auto";
 			const websocketDisabledForSession = transport !== "sse" && isWebSocketSseFallbackActive(options?.sessionId);
@@ -254,55 +276,74 @@ export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses"
 
 			if (transport !== "sse" && !websocketDisabledForSession) {
 				let websocketStarted = false;
-				try {
-					await processWebSocketStream(
-						resolveCodexWebSocketUrl(model.baseUrl),
-						body,
-						websocketHeaders,
-						output,
-						stream,
-						model,
-						() => {
-							websocketStarted = true;
-						},
-						idleTimeoutMs,
-						websocketConnectTimeoutMs,
-						options,
-					);
+				let retriedWebSocketConnectionLimit = false;
+				while (true) {
+					websocketStarted = false;
+					try {
+						await processWebSocketStream(
+							resolveCodexWebSocketUrl(model.baseUrl),
+							body,
+							websocketHeaders,
+							output,
+							stream,
+							model,
+							() => {
+								websocketStarted = true;
+							},
+							httpTimeoutMs,
+							websocketConnectTimeoutMs,
+							options,
+						);
 
-					if (options?.signal?.aborted) {
-						throw new Error("Request was aborted");
+						if (options?.signal?.aborted) {
+							throw new Error("Request was aborted");
+						}
+						stream.push({
+							type: "done",
+							reason: output.stopReason as "stop" | "length" | "toolUse",
+							message: output,
+						});
+						stream.end();
+						return;
+					} catch (error) {
+						const aborted = options?.signal?.aborted;
+						const connectionLimitBeforeStart = !websocketStarted && isWebSocketConnectionLimitReachedError(error);
+						if (!aborted && connectionLimitBeforeStart && !retriedWebSocketConnectionLimit) {
+							retriedWebSocketConnectionLimit = true;
+							continue;
+						}
+						if (aborted || (isCodexNonTransportError(error) && !connectionLimitBeforeStart)) {
+							throw error;
+						}
+						appendAssistantMessageDiagnostic(
+							output,
+							createAssistantMessageDiagnostic("provider_transport_failure", error, {
+								configuredTransport: transport,
+								fallbackTransport: websocketStarted ? undefined : "sse",
+								eventsEmitted: websocketStarted,
+								phase: websocketStarted ? "after_message_stream_start" : "before_message_stream_start",
+								requestBytes: new TextEncoder().encode(bodyJson).byteLength,
+							}),
+						);
+						recordWebSocketFailure(options?.sessionId, error);
+						if (websocketStarted) {
+							throw error;
+						}
+						recordWebSocketSseFallback(options?.sessionId);
+						break;
 					}
-					stream.push({
-						type: "done",
-						reason: output.stopReason as "stop" | "length" | "toolUse",
-						message: output,
-					});
-					stream.end();
-					return;
-				} catch (error) {
-					const aborted = options?.signal?.aborted;
-					if (aborted || isCodexNonTransportError(error)) {
-						throw error;
-					}
-					appendAssistantMessageDiagnostic(
-						output,
-						createAssistantMessageDiagnostic("provider_transport_failure", error, {
-							configuredTransport: transport,
-							fallbackTransport: websocketStarted ? undefined : "sse",
-							eventsEmitted: websocketStarted,
-							phase: websocketStarted ? "after_message_stream_start" : "before_message_stream_start",
-							requestBytes: new TextEncoder().encode(bodyJson).byteLength,
-						}),
-					);
-					recordWebSocketFailure(options?.sessionId, error);
-					if (websocketStarted) {
-						throw error;
-					}
-					recordWebSocketSseFallback(options?.sessionId);
 				}
 			}
 
+			// Compress the request body once for the SSE path. The Codex backend
+			// decodes Content-Encoding: zstd; the WebSocket transport above sends the
+			// uncompressed JSON frame, matching the official Codex client.
+			const compressedBody = compressRequestBodyZstd(bodyJson);
+			if (compressedBody) {
+				sseHeaders.set("content-encoding", "zstd");
+			}
+			const sseBody: Uint8Array | string = compressedBody ?? bodyJson;
+
 			// Fetch with retry logic for rate limits and transient errors
 			let response: Response | undefined;
 			let lastError: Error | undefined;
@@ -314,21 +355,23 @@ export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses"
 				}
 
 				try {
-					const headerTimeout = createSSEHeaderTimeout();
-					const combinedSignal = combineAbortSignals([options?.signal, headerTimeout.signal]);
+					const headerTimeoutSignal =
+						httpTimeoutMs !== undefined && httpTimeoutMs > 0 ? AbortSignal.timeout(httpTimeoutMs) : undefined;
+					const combinedSignal = combineAbortSignals([options?.signal, headerTimeoutSignal]);
 					try {
 						response = await fetch(resolveCodexUrl(model.baseUrl), {
 							method: "POST",
 							headers: sseHeaders,
-							body: bodyJson,
+							body: sseBody,
 							signal: combinedSignal.signal,
 						});
 					} catch (error) {
-						const timeoutError = headerTimeout.error();
-						throw timeoutError && !options?.signal?.aborted ? timeoutError : error;
+						if (headerTimeoutSignal?.aborted && !options?.signal?.aborted) {
+							throw new Error(`Codex SSE response headers timed out after ${httpTimeoutMs}ms`);
+						}
+						throw error;
 					} finally {
 						combinedSignal.cleanup();
-						headerTimeout.clear();
 					}
 					await options?.onResponse?.(
 						{ status: response.status, headers: headersToRecord(response.headers) },
@@ -400,7 +443,7 @@ export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses"
 				delete (block as { partialJson?: string }).partialJson;
 			}
 			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
-			output.errorMessage = error instanceof Error ? error.message : String(error);
+			output.errorMessage = formatProviderError(normalizeProviderError(error));
 			stream.push({ type: "error", reason: output.stopReason, error: output });
 			stream.end();
 		}
@@ -409,7 +452,7 @@ export const streamOpenAICodexResponses: StreamFunction<"openai-codex-responses"
 	return stream;
 };
 
-export const streamSimpleOpenAICodexResponses: StreamFunction<"openai-codex-responses", SimpleStreamOptions> = (
+export const streamSimple: StreamFunction<"openai-codex-responses", SimpleStreamOptions> = (
 	model: Model<"openai-codex-responses">,
 	context: Context,
 	options?: SimpleStreamOptions,
@@ -419,24 +462,16 @@ export const streamSimpleOpenAICodexResponses: StreamFunction<"openai-codex-resp
 		throw new Error(`No API key for provider: ${model.provider}`);
 	}
 
-	const base = buildBaseOptions(model, options, apiKey);
+	const base = buildBaseOptions(model, context, options, apiKey);
 	const clampedReasoning = options?.reasoning ? clampThinkingLevel(model, options.reasoning) : undefined;
 	const reasoningEffort = clampedReasoning === "off" ? undefined : clampedReasoning;
 
-	return streamOpenAICodexResponses(model, context, {
+	return stream(model, context, {
 		...base,
 		reasoningEffort,
 	} satisfies OpenAICodexResponsesOptions);
 };
 
-export function register(): void {
-	registerApiProvider({
-		api: "openai-codex-responses",
-		stream: streamOpenAICodexResponses,
-		streamSimple: streamSimpleOpenAICodexResponses,
-	});
-}
-
 // ============================================================================
 // Request Building
 // ============================================================================
@@ -591,16 +626,32 @@ function isCodexNonTransportError(error: unknown): boolean {
 	return error instanceof CodexApiError || error instanceof CodexProtocolError;
 }
 
+function isWebSocketConnectionLimitReachedError(error: unknown): boolean {
+	return error instanceof CodexApiError && error.code === WEBSOCKET_CONNECTION_LIMIT_REACHED_CODE;
+}
+
+function extractCodexEventError(event: Record<string, unknown>): { code?: string; message?: string } {
+	const nested = event.error && typeof event.error === "object" ? (event.error as Record<string, unknown>) : undefined;
+	return {
+		code: typeof event.code === "string" ? event.code : typeof nested?.code === "string" ? nested.code : undefined,
+		message:
+			typeof event.message === "string"
+				? event.message
+				: typeof nested?.message === "string"
+					? nested.message
+					: undefined,
+	};
+}
+
 async function* mapCodexEvents(events: AsyncIterable<Record<string, unknown>>): AsyncGenerator<ResponseStreamEvent> {
 	for await (const event of events) {
 		const type = typeof event.type === "string" ? event.type : undefined;
 		if (!type) continue;
 
 		if (type === "error") {
-			const code = (event as { code?: string }).code || "";
-			const message = (event as { message?: string }).message || "";
+			const { code, message } = extractCodexEventError(event);
 			throw new CodexApiError(`Codex error: ${message || code || JSON.stringify(event)}`, {
-				code: code || undefined,
+				code,
 				payload: event,
 			});
 		}
@@ -699,6 +750,7 @@ async function* parseSSE(response: Response, signal?: AbortSignal): AsyncGenerat
 
 const OPENAI_BETA_RESPONSES_WEBSOCKETS = "responses_websockets=2026-02-06";
 const SESSION_WEBSOCKET_CACHE_TTL_MS = 5 * 60 * 1000;
+const SESSION_WEBSOCKET_MAX_AGE_MS = 55 * 60 * 1000;
 
 type WebSocketEventType = "open" | "message" | "error" | "close";
 type WebSocketListener = (event: unknown) => void;
@@ -719,6 +771,7 @@ interface CachedWebSocketContinuationState {
 interface CachedWebSocketConnection {
 	socket: WebSocketLike;
 	busy: boolean;
+	createdAt: number;
 	idleTimer?: ReturnType<typeof setTimeout>;
 	continuation?: CachedWebSocketContinuationState;
 }
@@ -883,6 +936,10 @@ function isWebSocketReusable(socket: WebSocketLike): boolean {
 	return readyState === undefined || readyState === 1;
 }
 
+function isWebSocketSessionExpired(entry: CachedWebSocketConnection): boolean {
+	return Date.now() - entry.createdAt >= SESSION_WEBSOCKET_MAX_AGE_MS;
+}
+
 function closeWebSocketSilently(socket: WebSocketLike, code = 1000, reason = "done"): void {
 	try {
 		socket.close(code, reason);
@@ -1006,7 +1063,10 @@ async function acquireWebSocket(
 			clearTimeout(cached.idleTimer);
 			cached.idleTimer = undefined;
 		}
-		if (!cached.busy && isWebSocketReusable(cached.socket)) {
+		if (!cached.busy && isWebSocketSessionExpired(cached)) {
+			closeWebSocketSilently(cached.socket, 1000, "connection_age_limit");
+			websocketSessionCache.delete(sessionId);
+		} else if (!cached.busy && isWebSocketReusable(cached.socket)) {
 			cached.busy = true;
 			return {
 				socket: cached.socket,
@@ -1040,7 +1100,7 @@ async function acquireWebSocket(
 	}
 
 	const socket = await connectWebSocket(url, headers, signal, connectTimeoutMs, env);
-	const entry: CachedWebSocketConnection = { socket, busy: true };
+	const entry: CachedWebSocketConnection = { socket, busy: true, createdAt: Date.now() };
 	websocketSessionCache.set(sessionId, entry);
 	return {
 		socket,
@@ -1449,13 +1509,17 @@ function createCodexRequestId(): string {
 
 function buildBaseCodexHeaders(
 	initHeaders: Record<string, string> | undefined,
-	additionalHeaders: Record<string, string> | undefined,
+	additionalHeaders: ProviderHeaders | undefined,
 	accountId: string,
 	token: string,
 ): Headers {
 	const headers = new Headers(initHeaders);
 	for (const [key, value] of Object.entries(additionalHeaders || {})) {
-		headers.set(key, value);
+		if (value === null) {
+			headers.delete(key);
+		} else {
+			headers.set(key, value);
+		}
 	}
 	headers.set("Authorization", `Bearer ${token}`);
 	headers.set("chatgpt-account-id", accountId);
@@ -1467,7 +1531,7 @@ function buildBaseCodexHeaders(
 
 function buildSSEHeaders(
 	initHeaders: Record<string, string> | undefined,
-	additionalHeaders: Record<string, string> | undefined,
+	additionalHeaders: ProviderHeaders | undefined,
 	accountId: string,
 	token: string,
 	sessionId?: string,
@@ -1487,7 +1551,7 @@ function buildSSEHeaders(
 
 function buildWebSocketHeaders(
 	initHeaders: Record<string, string> | undefined,
-	additionalHeaders: Record<string, string> | undefined,
+	additionalHeaders: ProviderHeaders | undefined,
 	accountId: string,
 	token: string,
 	requestId: string,

packages/ai/src/api/openai-completions.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const openAICompletionsApi = (): ProviderStreams => lazyApi(() => import("./openai-completions.ts"));

packages/ai/src/api/openai-completions.ts

@@ -10,7 +10,6 @@ import type {
 	ChatCompletionSystemMessageParam,
 	ChatCompletionToolMessageParam,
 } from "openai/resources/chat/completions.js";
-import { registerApiProvider } from "../api-registry.ts";
 import { calculateCost, clampThinkingLevel } from "../models.ts";
 import type {
 	AssistantMessage,
@@ -22,6 +21,7 @@ import type {
 	Model,
 	OpenAICompletionsCompat,
 	ProviderEnv,
+	ProviderHeaders,
 	SimpleStreamOptions,
 	StopReason,
 	StreamFunction,
@@ -32,12 +32,12 @@ import type {
 	ToolCall,
 	ToolResultMessage,
 } from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
 import { AssistantMessageEventStream } from "../utils/event-stream.ts";
 import { headersToRecord } from "../utils/headers.ts";
 import { parseStreamingJson } from "../utils/json-parse.ts";
 import { getProviderEnvValue } from "../utils/provider-env.ts";
 import { sanitizeSurrogates } from "../utils/sanitize-unicode.ts";
-import { isCloudflareProvider, resolveCloudflareBaseUrl } from "./cloudflare.ts";
 import { buildCopilotDynamicHeaders, hasCopilotVisionInput } from "./github-copilot-headers.ts";
 import { clampOpenAIPromptCacheKey } from "./openai-prompt-cache.ts";
 import { buildBaseOptions } from "./simple-options.ts";
@@ -48,6 +48,21 @@ import { transformMessages } from "./transform-messages.ts";
  * This is needed because Anthropic (via proxy) requires the tools param
  * to be present when messages include tool_calls or tool role messages.
  */
+function hasHeader(headers: ProviderHeaders | undefined, name: string): boolean {
+	if (!headers) return false;
+	const expected = name.toLowerCase();
+	for (const [key, value] of Object.entries(headers)) {
+		if (key.toLowerCase() === expected && value !== null && value.trim().length > 0) return true;
+	}
+	return false;
+}
+
+function getClientApiKey(provider: string, apiKey: string | undefined, headers: ProviderHeaders | undefined): string {
+	if (apiKey) return apiKey;
+	if (hasHeader(headers, "authorization") || hasHeader(headers, "cf-aig-authorization")) return "unused";
+	throw new Error(`No API key for provider: ${provider}`);
+}
+
 function hasToolHistory(messages: Message[]): boolean {
 	for (const msg of messages) {
 		if (msg.role === "toolResult") {
@@ -134,7 +149,7 @@ function resolveCacheRetention(cacheRetention?: CacheRetention, env?: ProviderEn
 	return "short";
 }
 
-export const streamOpenAICompletions: StreamFunction<"openai-completions", OpenAICompletionsOptions> = (
+export const stream: StreamFunction<"openai-completions", OpenAICompletionsOptions> = (
 	model: Model<"openai-completions">,
 	context: Context,
 	options?: OpenAICompletionsOptions,
@@ -161,14 +176,11 @@ export const streamOpenAICompletions: StreamFunction<"openai-completions", OpenA
 		};
 
 		try {
-			const apiKey = options?.apiKey;
-			if (!apiKey) {
-				throw new Error(`No API key for provider: ${model.provider}`);
-			}
+			const apiKey = getClientApiKey(model.provider, options?.apiKey, options?.headers);
 			const compat = getCompat(model);
 			const cacheRetention = resolveCacheRetention(options?.cacheRetention, options?.env);
 			const cacheSessionId = cacheRetention === "none" ? undefined : options?.sessionId;
-			const client = createClient(model, context, apiKey, options?.headers, cacheSessionId, compat, options?.env);
+			const client = createClient(model, context, apiKey, options?.headers, cacheSessionId, compat);
 			let params = buildParams(model, context, options, compat, cacheRetention);
 			const nextParams = await options?.onPayload?.(params, model);
 			if (nextParams !== undefined) {
@@ -452,10 +464,15 @@ export const streamOpenAICompletions: StreamFunction<"openai-completions", OpenA
 				delete (block as { streamIndex?: number }).streamIndex;
 			}
 			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
-			output.errorMessage = error instanceof Error ? error.message : JSON.stringify(error);
+			output.errorMessage = formatProviderError(normalizeProviderError(error));
 			// Some providers via OpenRouter give additional information in this field.
+			// normalizeProviderError already stringifies the parsed body (error.error)
+			// into errorMessage, so only append the raw metadata when it is not already
+			// present to avoid double-printing it.
 			const rawMetadata = (error as any)?.error?.metadata?.raw;
-			if (rawMetadata) output.errorMessage += `\n${rawMetadata}`;
+			if (rawMetadata && !output.errorMessage.includes(String(rawMetadata))) {
+				output.errorMessage += `\n${rawMetadata}`;
+			}
 			stream.push({ type: "error", reason: output.stopReason, error: output });
 			stream.end();
 		}
@@ -464,46 +481,34 @@ export const streamOpenAICompletions: StreamFunction<"openai-completions", OpenA
 	return stream;
 };
 
-export const streamSimpleOpenAICompletions: StreamFunction<"openai-completions", SimpleStreamOptions> = (
+export const streamSimple: StreamFunction<"openai-completions", SimpleStreamOptions> = (
 	model: Model<"openai-completions">,
 	context: Context,
 	options?: SimpleStreamOptions,
 ): AssistantMessageEventStream => {
-	const apiKey = options?.apiKey;
-	if (!apiKey) {
-		throw new Error(`No API key for provider: ${model.provider}`);
-	}
+	getClientApiKey(model.provider, options?.apiKey, options?.headers);
 
-	const base = buildBaseOptions(model, options, apiKey);
+	const base = buildBaseOptions(model, context, options, options?.apiKey);
 	const clampedReasoning = options?.reasoning ? clampThinkingLevel(model, options.reasoning) : undefined;
 	const reasoningEffort = clampedReasoning === "off" ? undefined : clampedReasoning;
 	const toolChoice = (options as OpenAICompletionsOptions | undefined)?.toolChoice;
 
-	return streamOpenAICompletions(model, context, {
+	return stream(model, context, {
 		...base,
 		reasoningEffort,
 		toolChoice,
 	} satisfies OpenAICompletionsOptions);
 };
 
-export function register(): void {
-	registerApiProvider({
-		api: "openai-completions",
-		stream: streamOpenAICompletions,
-		streamSimple: streamSimpleOpenAICompletions,
-	});
-}
-
 function createClient(
 	model: Model<"openai-completions">,
 	context: Context,
 	apiKey: string,
-	optionsHeaders?: Record<string, string>,
+	optionsHeaders?: ProviderHeaders,
 	sessionId?: string,
 	compat: ResolvedOpenAICompletionsCompat = getCompat(model),
-	env?: ProviderEnv,
 ) {
-	const headers = { ...model.headers };
+	const headers: ProviderHeaders = { ...model.headers };
 	if (model.provider === "github-copilot") {
 		const hasImages = hasCopilotVisionInput(context.messages);
 		const copilotHeaders = buildCopilotDynamicHeaders({
@@ -524,20 +529,11 @@ function createClient(
 		Object.assign(headers, optionsHeaders);
 	}
 
-	const defaultHeaders =
-		model.provider === "cloudflare-ai-gateway"
-			? {
-					...headers,
-					Authorization: headers.Authorization ?? null,
-					"cf-aig-authorization": `Bearer ${apiKey}`,
-				}
-			: headers;
-
 	return new OpenAI({
 		apiKey,
-		baseURL: isCloudflareProvider(model.provider) ? resolveCloudflareBaseUrl(model, env) : model.baseUrl,
+		baseURL: model.baseUrl,
 		dangerouslyAllowBrowser: true,
-		defaultHeaders,
+		defaultHeaders: headers,
 	});
 }
 
@@ -603,10 +599,10 @@ function buildParams(
 
 	if (compat.thinkingFormat === "zai" && model.reasoning) {
 		const zaiParams = params as Omit<typeof params, "reasoning_effort"> & {
-			thinking?: { type: "enabled" | "disabled" };
+			thinking?: { type: "enabled" | "disabled"; clear_thinking?: boolean };
 			reasoning_effort?: string;
 		};
-		zaiParams.thinking = { type: options?.reasoningEffort ? "enabled" : "disabled" };
+		zaiParams.thinking = options?.reasoningEffort ? { type: "enabled", clear_thinking: false } : { type: "disabled" };
 		if (options?.reasoningEffort && compat.supportsReasoningEffort) {
 			const mappedEffort = model.thinkingLevelMap?.[options.reasoningEffort];
 			const effort = mappedEffort === undefined ? options.reasoningEffort : mappedEffort;
@@ -683,7 +679,7 @@ function buildParams(
 	}
 
 	// Vercel AI Gateway provider routing preferences
-	if (model.baseUrl.includes("ai-gateway.vercel.sh") && model.compat?.vercelGatewayRouting) {
+	if (model.compat?.vercelGatewayRouting) {
 		const routing = model.compat.vercelGatewayRouting;
 		if (routing.only || routing.order) {
 			const gatewayOptions: Record<string, string[]> = {};
@@ -1037,10 +1033,11 @@ export function convertMessages(
 
 				// Always send tool result with text (or placeholder if only images)
 				const hasText = textResult.length > 0;
+				const toolResultText = hasText ? textResult : hasImages ? "(see attached image)" : "(no tool output)";
 				// Some providers require the 'name' field in tool results
 				const toolResultMsg: ChatCompletionToolMessageParam = {
 					role: "tool",
-					content: sanitizeSurrogates(hasText ? textResult : "(see attached image)"),
+					content: sanitizeSurrogates(toolResultText),
 					tool_call_id: toolMsg.toolCallId,
 				};
 				if (compat.requiresToolResultName && toolMsg.toolName) {
@@ -1117,6 +1114,7 @@ function parseChunkUsage(
 		completion_tokens?: number;
 		prompt_cache_hit_tokens?: number;
 		prompt_tokens_details?: { cached_tokens?: number; cache_write_tokens?: number };
+		completion_tokens_details?: { reasoning_tokens?: number };
 	},
 	model: Model<"openai-completions">,
 ): AssistantMessage["usage"] {
@@ -1140,6 +1138,7 @@ function parseChunkUsage(
 		output: outputTokens,
 		cacheRead: cacheReadTokens,
 		cacheWrite: cacheWriteTokens,
+		reasoning: rawUsage.completion_tokens_details?.reasoning_tokens || 0,
 		totalTokens: input + outputTokens + cacheReadTokens + cacheWriteTokens,
 		cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
 	};
@@ -1174,9 +1173,9 @@ function mapStopReason(reason: ChatCompletionChunk.Choice["finish_reason"] | str
 }
 
 /**
- * Detect compatibility settings from provider and baseUrl for known providers.
- * Provider takes precedence over URL-based detection since it's explicitly configured.
- * Returns a fully resolved OpenAICompletionsCompat object with all fields set.
+ * Auto-detect compatibility settings from provider name and baseUrl.
+ * Used as the base when model.compat is not set; explicit model.compat
+ * entries override these detected values.
  */
 function detectCompat(model: Model<"openai-completions">): ResolvedOpenAICompletionsCompat {
 	const provider = model.provider;
@@ -1263,7 +1262,7 @@ function detectCompat(model: Model<"openai-completions">): ResolvedOpenAIComplet
 
 /**
  * Get resolved compatibility settings for a model.
- * Uses explicit model.compat if provided, otherwise auto-detects from provider/URL.
+ * Auto-detects from provider/URL then overrides with explicit model.compat.
  */
 function getCompat(model: Model<"openai-completions">): ResolvedOpenAICompletionsCompat {
 	const detected = detectCompat(model);

packages/ai/src/api/openai-responses-shared.ts

@@ -3,11 +3,11 @@ import type {
 	Tool as OpenAITool,
 	ResponseCreateParamsStreaming,
 	ResponseFunctionCallOutputItemList,
-	ResponseFunctionToolCall,
 	ResponseInput,
 	ResponseInputContent,
 	ResponseInputImage,
 	ResponseInputText,
+	ResponseOutputItem,
 	ResponseOutputMessage,
 	ResponseReasoningItem,
 	ResponseStreamEvent,
@@ -251,7 +251,7 @@ export function convertResponsesMessages<TApi extends Api>(
 
 				output = contentParts;
 			} else {
-				output = sanitizeSurrogates(hasText ? textResult : "(see attached image)");
+				output = sanitizeSurrogates(hasText ? textResult : hasImages ? "(see attached image)" : "(no tool output)");
 			}
 
 			messages.push({
@@ -285,6 +285,13 @@ export function convertResponsesTools(tools: Tool[], options?: ConvertResponsesT
 // Stream processing
 // =============================================================================
 
+type StreamingToolCall = ToolCall & { partialJson: string };
+
+type ResponsesOutputSlot =
+	| { type: "thinking"; block: ThinkingContent; contentIndex: number }
+	| { type: "text"; block: TextContent; contentIndex: number }
+	| { type: "toolCall"; block: StreamingToolCall; contentIndex: number };
+
 export async function processResponsesStream<TApi extends Api>(
 	openaiStream: AsyncIterable<ResponseStreamEvent>,
 	output: AssistantMessage,
@@ -292,237 +299,222 @@ export async function processResponsesStream<TApi extends Api>(
 	model: Model<TApi>,
 	options?: OpenAIResponsesStreamOptions,
 ): Promise<void> {
-	let currentItem: ResponseReasoningItem | ResponseOutputMessage | ResponseFunctionToolCall | null = null;
-	let currentBlock: ThinkingContent | TextContent | (ToolCall & { partialJson: string }) | null = null;
-	const blocks = output.content;
-	const blockIndex = () => blocks.length - 1;
+	let sawTerminalResponseEvent = false;
+	const outputSlots = new Map<number, ResponsesOutputSlot>();
+	const getSlot = <TType extends ResponsesOutputSlot["type"]>(
+		outputIndex: number,
+		type: TType,
+	): Extract<ResponsesOutputSlot, { type: TType }> | undefined => {
+		const slot = outputSlots.get(outputIndex);
+		return slot?.type === type ? (slot as Extract<ResponsesOutputSlot, { type: TType }>) : undefined;
+	};
+	const createSlot = (outputIndex: number, item: ResponseOutputItem): ResponsesOutputSlot | undefined => {
+		if (item.type === "reasoning") {
+			const block: ThinkingContent = { type: "thinking", thinking: "" };
+			output.content.push(block);
+			const slot = {
+				type: "thinking",
+				block,
+				contentIndex: output.content.length - 1,
+			} satisfies ResponsesOutputSlot;
+			outputSlots.set(outputIndex, slot);
+			stream.push({ type: "thinking_start", contentIndex: slot.contentIndex, partial: output });
+			return slot;
+		}
+		if (item.type === "message") {
+			const block: TextContent = { type: "text", text: "" };
+			output.content.push(block);
+			const slot = { type: "text", block, contentIndex: output.content.length - 1 } satisfies ResponsesOutputSlot;
+			outputSlots.set(outputIndex, slot);
+			stream.push({ type: "text_start", contentIndex: slot.contentIndex, partial: output });
+			return slot;
+		}
+		if (item.type === "function_call") {
+			const block: StreamingToolCall = {
+				type: "toolCall",
+				id: `${item.call_id}|${item.id}`,
+				name: item.name,
+				arguments: {},
+				partialJson: item.arguments || "",
+			};
+			output.content.push(block);
+			const slot = {
+				type: "toolCall",
+				block,
+				contentIndex: output.content.length - 1,
+			} satisfies ResponsesOutputSlot;
+			outputSlots.set(outputIndex, slot);
+			stream.push({ type: "toolcall_start", contentIndex: slot.contentIndex, partial: output });
+			return slot;
+		}
+		return undefined;
+	};
+	const getOrCreateSlot = (outputIndex: number, item: ResponseOutputItem): ResponsesOutputSlot | undefined => {
+		return outputSlots.get(outputIndex) ?? createSlot(outputIndex, item);
+	};
+	const finalizeResponse = (
+		response: Extract<ResponseStreamEvent, { type: "response.completed" | "response.incomplete" }>["response"],
+	): void => {
+		sawTerminalResponseEvent = true;
+		if (response?.id) {
+			output.responseId = response.id;
+		}
+		if (response?.usage) {
+			const cachedTokens = response.usage.input_tokens_details?.cached_tokens || 0;
+			output.usage = {
+				// OpenAI includes cached tokens in input_tokens, so subtract to get non-cached input
+				input: (response.usage.input_tokens || 0) - cachedTokens,
+				output: response.usage.output_tokens || 0,
+				cacheRead: cachedTokens,
+				cacheWrite: 0,
+				reasoning: response.usage.output_tokens_details?.reasoning_tokens || 0,
+				totalTokens: response.usage.total_tokens || 0,
+				cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+			};
+		}
+		calculateCost(model, output.usage);
+		if (options?.applyServiceTierPricing) {
+			const serviceTier = options.resolveServiceTier
+				? options.resolveServiceTier(response?.service_tier, options.serviceTier)
+				: (response?.service_tier ?? options.serviceTier);
+			options.applyServiceTierPricing(output.usage, serviceTier);
+		}
+		// Map status to stop reason
+		output.stopReason = mapStopReason(response?.status);
+		if (output.content.some((b) => b.type === "toolCall") && output.stopReason === "stop") {
+			output.stopReason = "toolUse";
+		}
+	};
 
 	for await (const event of openaiStream) {
 		if (event.type === "response.created") {
 			output.responseId = event.response.id;
 		} else if (event.type === "response.output_item.added") {
-			const item = event.item;
-			if (item.type === "reasoning") {
-				currentItem = item;
-				currentBlock = { type: "thinking", thinking: "" };
-				output.content.push(currentBlock);
-				stream.push({ type: "thinking_start", contentIndex: blockIndex(), partial: output });
-			} else if (item.type === "message") {
-				currentItem = item;
-				currentBlock = { type: "text", text: "" };
-				output.content.push(currentBlock);
-				stream.push({ type: "text_start", contentIndex: blockIndex(), partial: output });
-			} else if (item.type === "function_call") {
-				currentItem = item;
-				currentBlock = {
-					type: "toolCall",
-					id: `${item.call_id}|${item.id}`,
-					name: item.name,
-					arguments: {},
-					partialJson: item.arguments || "",
-				};
-				output.content.push(currentBlock);
-				stream.push({ type: "toolcall_start", contentIndex: blockIndex(), partial: output });
-			}
-		} else if (event.type === "response.reasoning_summary_part.added") {
-			if (currentItem && currentItem.type === "reasoning") {
-				currentItem.summary = currentItem.summary || [];
-				currentItem.summary.push(event.part);
-			}
+			createSlot(event.output_index, event.item);
 		} else if (event.type === "response.reasoning_summary_text.delta") {
-			if (currentItem?.type === "reasoning" && currentBlock?.type === "thinking") {
-				currentItem.summary = currentItem.summary || [];
-				const lastPart = currentItem.summary[currentItem.summary.length - 1];
-				if (lastPart) {
-					currentBlock.thinking += event.delta;
-					lastPart.text += event.delta;
-					stream.push({
-						type: "thinking_delta",
-						contentIndex: blockIndex(),
-						delta: event.delta,
-						partial: output,
-					});
-				}
-			}
+			const slot = getSlot(event.output_index, "thinking");
+			if (!slot) continue;
+			slot.block.thinking += event.delta;
+			stream.push({
+				type: "thinking_delta",
+				contentIndex: slot.contentIndex,
+				delta: event.delta,
+				partial: output,
+			});
 		} else if (event.type === "response.reasoning_summary_part.done") {
-			if (currentItem?.type === "reasoning" && currentBlock?.type === "thinking") {
-				currentItem.summary = currentItem.summary || [];
-				const lastPart = currentItem.summary[currentItem.summary.length - 1];
-				if (lastPart) {
-					currentBlock.thinking += "\n\n";
-					lastPart.text += "\n\n";
-					stream.push({
-						type: "thinking_delta",
-						contentIndex: blockIndex(),
-						delta: "\n\n",
-						partial: output,
-					});
-				}
-			}
+			const slot = getSlot(event.output_index, "thinking");
+			if (!slot) continue;
+			slot.block.thinking += "\n\n";
+			stream.push({
+				type: "thinking_delta",
+				contentIndex: slot.contentIndex,
+				delta: "\n\n",
+				partial: output,
+			});
 		} else if (event.type === "response.reasoning_text.delta") {
-			if (currentItem?.type === "reasoning" && currentBlock?.type === "thinking") {
-				currentBlock.thinking += event.delta;
-				stream.push({
-					type: "thinking_delta",
-					contentIndex: blockIndex(),
-					delta: event.delta,
-					partial: output,
-				});
-			}
-		} else if (event.type === "response.content_part.added") {
-			if (currentItem?.type === "message") {
-				currentItem.content = currentItem.content || [];
-				// Filter out ReasoningText, only accept output_text and refusal
-				if (event.part.type === "output_text" || event.part.type === "refusal") {
-					currentItem.content.push(event.part);
-				}
-			}
+			const slot = getSlot(event.output_index, "thinking");
+			if (!slot) continue;
+			slot.block.thinking += event.delta;
+			stream.push({
+				type: "thinking_delta",
+				contentIndex: slot.contentIndex,
+				delta: event.delta,
+				partial: output,
+			});
 		} else if (event.type === "response.output_text.delta") {
-			if (currentItem?.type === "message" && currentBlock?.type === "text") {
-				if (!currentItem.content || currentItem.content.length === 0) {
-					continue;
-				}
-				const lastPart = currentItem.content[currentItem.content.length - 1];
-				if (lastPart?.type === "output_text") {
-					currentBlock.text += event.delta;
-					lastPart.text += event.delta;
-					stream.push({
-						type: "text_delta",
-						contentIndex: blockIndex(),
-						delta: event.delta,
-						partial: output,
-					});
-				}
-			}
+			const slot = getSlot(event.output_index, "text");
+			if (!slot) continue;
+			slot.block.text += event.delta;
+			stream.push({
+				type: "text_delta",
+				contentIndex: slot.contentIndex,
+				delta: event.delta,
+				partial: output,
+			});
 		} else if (event.type === "response.refusal.delta") {
-			if (currentItem?.type === "message" && currentBlock?.type === "text") {
-				if (!currentItem.content || currentItem.content.length === 0) {
-					continue;
-				}
-				const lastPart = currentItem.content[currentItem.content.length - 1];
-				if (lastPart?.type === "refusal") {
-					currentBlock.text += event.delta;
-					lastPart.refusal += event.delta;
+			const slot = getSlot(event.output_index, "text");
+			if (!slot) continue;
+			slot.block.text += event.delta;
+			stream.push({
+				type: "text_delta",
+				contentIndex: slot.contentIndex,
+				delta: event.delta,
+				partial: output,
+			});
+		} else if (event.type === "response.function_call_arguments.delta") {
+			const slot = getSlot(event.output_index, "toolCall");
+			if (!slot) continue;
+			slot.block.partialJson += event.delta;
+			slot.block.arguments = parseStreamingJson(slot.block.partialJson);
+			stream.push({
+				type: "toolcall_delta",
+				contentIndex: slot.contentIndex,
+				delta: event.delta,
+				partial: output,
+			});
+		} else if (event.type === "response.function_call_arguments.done") {
+			const slot = getSlot(event.output_index, "toolCall");
+			if (!slot) continue;
+			const previousPartialJson = slot.block.partialJson;
+			slot.block.partialJson = event.arguments;
+			slot.block.arguments = parseStreamingJson(slot.block.partialJson);
+
+			if (event.arguments.startsWith(previousPartialJson)) {
+				const delta = event.arguments.slice(previousPartialJson.length);
+				if (delta.length > 0) {
 					stream.push({
-						type: "text_delta",
-						contentIndex: blockIndex(),
-						delta: event.delta,
+						type: "toolcall_delta",
+						contentIndex: slot.contentIndex,
+						delta,
 						partial: output,
 					});
 				}
 			}
-		} else if (event.type === "response.function_call_arguments.delta") {
-			if (currentItem?.type === "function_call" && currentBlock?.type === "toolCall") {
-				currentBlock.partialJson += event.delta;
-				currentBlock.arguments = parseStreamingJson(currentBlock.partialJson);
-				stream.push({
-					type: "toolcall_delta",
-					contentIndex: blockIndex(),
-					delta: event.delta,
-					partial: output,
-				});
-			}
-		} else if (event.type === "response.function_call_arguments.done") {
-			if (currentItem?.type === "function_call" && currentBlock?.type === "toolCall") {
-				const previousPartialJson = currentBlock.partialJson;
-				currentBlock.partialJson = event.arguments;
-				currentBlock.arguments = parseStreamingJson(currentBlock.partialJson);
-
-				if (event.arguments.startsWith(previousPartialJson)) {
-					const delta = event.arguments.slice(previousPartialJson.length);
-					if (delta.length > 0) {
-						stream.push({
-							type: "toolcall_delta",
-							contentIndex: blockIndex(),
-							delta,
-							partial: output,
-						});
-					}
-				}
-			}
 		} else if (event.type === "response.output_item.done") {
 			const item = event.item;
+			const slot = getOrCreateSlot(event.output_index, item);
 
-			if (item.type === "reasoning" && currentBlock?.type === "thinking") {
+			if (item.type === "reasoning" && slot?.type === "thinking") {
 				const summaryText = item.summary?.map((s) => s.text).join("\n\n") || "";
 				const contentText = item.content?.map((c) => c.text).join("\n\n") || "";
-				currentBlock.thinking = summaryText || contentText || currentBlock.thinking;
-				currentBlock.thinkingSignature = JSON.stringify(item);
+				slot.block.thinking = summaryText || contentText || slot.block.thinking;
+				slot.block.thinkingSignature = JSON.stringify(item);
 				stream.push({
 					type: "thinking_end",
-					contentIndex: blockIndex(),
-					content: currentBlock.thinking,
+					contentIndex: slot.contentIndex,
+					content: slot.block.thinking,
 					partial: output,
 				});
-				currentBlock = null;
-			} else if (item.type === "message" && currentBlock?.type === "text") {
-				currentBlock.text =
-					item.content?.map((c) => (c.type === "output_text" ? c.text : c.refusal)).join("") || "";
-				currentBlock.textSignature = encodeTextSignatureV1(item.id, item.phase ?? undefined);
+				outputSlots.delete(event.output_index);
+			} else if (item.type === "message" && slot?.type === "text") {
+				slot.block.text = item.content?.map((c) => (c.type === "output_text" ? c.text : c.refusal)).join("") || "";
+				slot.block.textSignature = encodeTextSignatureV1(item.id, item.phase ?? undefined);
 				stream.push({
 					type: "text_end",
-					contentIndex: blockIndex(),
-					content: currentBlock.text,
+					contentIndex: slot.contentIndex,
+					content: slot.block.text,
 					partial: output,
 				});
-				currentBlock = null;
-			} else if (item.type === "function_call") {
-				const args =
-					currentBlock?.type === "toolCall" && currentBlock.partialJson
-						? parseStreamingJson(currentBlock.partialJson)
-						: parseStreamingJson(item.arguments || "{}");
-
-				let toolCall: ToolCall;
-				if (currentBlock?.type === "toolCall") {
-					// Finalize in-place and strip the scratch buffer so replay only
-					// carries parsed arguments.
-					currentBlock.arguments = args;
-					delete (currentBlock as { partialJson?: string }).partialJson;
-					toolCall = currentBlock;
-				} else {
-					toolCall = {
-						type: "toolCall",
-						id: `${item.call_id}|${item.id}`,
-						name: item.name,
-						arguments: args,
-					};
-				}
-
-				currentBlock = null;
-				stream.push({ type: "toolcall_end", contentIndex: blockIndex(), toolCall, partial: output });
-			}
-		} else if (event.type === "response.completed") {
-			const response = event.response;
-			if (response?.id) {
-				output.responseId = response.id;
-			}
-			if (response?.usage) {
-				const cachedTokens = response.usage.input_tokens_details?.cached_tokens || 0;
-				output.usage = {
-					// OpenAI includes cached tokens in input_tokens, so subtract to get non-cached input
-					input: (response.usage.input_tokens || 0) - cachedTokens,
-					output: response.usage.output_tokens || 0,
-					cacheRead: cachedTokens,
-					cacheWrite: 0,
-					totalTokens: response.usage.total_tokens || 0,
-					cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
-				};
-			}
-			calculateCost(model, output.usage);
-			if (options?.applyServiceTierPricing) {
-				const serviceTier = options.resolveServiceTier
-					? options.resolveServiceTier(response?.service_tier, options.serviceTier)
-					: (response?.service_tier ?? options.serviceTier);
-				options.applyServiceTierPricing(output.usage, serviceTier);
-			}
-			// Map status to stop reason
-			output.stopReason = mapStopReason(response?.status);
-			if (output.content.some((b) => b.type === "toolCall") && output.stopReason === "stop") {
-				output.stopReason = "toolUse";
+				outputSlots.delete(event.output_index);
+			} else if (item.type === "function_call" && slot?.type === "toolCall") {
+				slot.block.arguments = parseStreamingJson(item.arguments || slot.block.partialJson || "{}");
+				// Finalize in-place and strip the scratch buffer so replay only
+				// carries parsed arguments.
+				delete (slot.block as { partialJson?: string }).partialJson;
+				stream.push({
+					type: "toolcall_end",
+					contentIndex: slot.contentIndex,
+					toolCall: slot.block,
+					partial: output,
+				});
+				outputSlots.delete(event.output_index);
 			}
+		} else if (event.type === "response.completed" || event.type === "response.incomplete") {
+			finalizeResponse(event.response);
 		} else if (event.type === "error") {
 			throw new Error(`Error Code ${event.code}: ${event.message}` || "Unknown error");
 		} else if (event.type === "response.failed") {
+			sawTerminalResponseEvent = true;
 			const error = event.response?.error;
 			const details = event.response?.incomplete_details;
 			const msg = error
@@ -533,6 +525,9 @@ export async function processResponsesStream<TApi extends Api>(
 			throw new Error(msg);
 		}
 	}
+	if (!sawTerminalResponseEvent) {
+		throw new Error("OpenAI Responses stream ended before a terminal response event");
+	}
 }
 
 function mapStopReason(status: OpenAI.Responses.ResponseStatus | undefined): StopReason {

packages/ai/src/api/openai-responses.lazy.ts

@@ -0,0 +1,4 @@
+import type { ProviderStreams } from "../types.ts";
+import { lazyApi } from "./lazy.ts";
+
+export const openAIResponsesApi = (): ProviderStreams => lazyApi(() => import("./openai-responses.ts"));

packages/ai/src/api/openai-responses.ts

@@ -1,6 +1,5 @@
 import OpenAI from "openai";
 import type { ResponseCreateParamsStreaming } from "openai/resources/responses/responses.js";
-import { registerApiProvider } from "../api-registry.ts";
 import { clampThinkingLevel } from "../models.ts";
 import type {
 	Api,
@@ -10,21 +9,39 @@ import type {
 	Model,
 	OpenAIResponsesCompat,
 	ProviderEnv,
+	ProviderHeaders,
 	SimpleStreamOptions,
 	StreamFunction,
 	StreamOptions,
 	Usage,
 } from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
 import { AssistantMessageEventStream } from "../utils/event-stream.ts";
 import { headersToRecord } from "../utils/headers.ts";
 import { getProviderEnvValue } from "../utils/provider-env.ts";
-import { isCloudflareProvider, resolveCloudflareBaseUrl } from "./cloudflare.ts";
 import { buildCopilotDynamicHeaders, hasCopilotVisionInput } from "./github-copilot-headers.ts";
 import { clampOpenAIPromptCacheKey } from "./openai-prompt-cache.ts";
 import { convertResponsesMessages, convertResponsesTools, processResponsesStream } from "./openai-responses-shared.ts";
 import { buildBaseOptions } from "./simple-options.ts";
 
 const OPENAI_TOOL_CALL_PROVIDERS = new Set(["openai", "openai-codex", "opencode"]);
+// OpenAI Responses rejects max_output_tokens below 16: https://github.com/earendil-works/pi/issues/6265
+const OPENAI_RESPONSES_MIN_OUTPUT_TOKENS = 16;
+
+function hasHeader(headers: ProviderHeaders | undefined, name: string): boolean {
+	if (!headers) return false;
+	const expected = name.toLowerCase();
+	for (const [key, value] of Object.entries(headers)) {
+		if (key.toLowerCase() === expected && value !== null && value.trim().length > 0) return true;
+	}
+	return false;
+}
+
+function getClientApiKey(provider: string, apiKey: string | undefined, headers: ProviderHeaders | undefined): string {
+	if (apiKey) return apiKey;
+	if (hasHeader(headers, "authorization") || hasHeader(headers, "cf-aig-authorization")) return "unused";
+	throw new Error(`No API key for provider: ${provider}`);
+}
 
 /**
  * Resolve cache retention preference.
@@ -56,19 +73,7 @@ function getPromptCacheRetention(
 }
 
 function formatOpenAIResponsesError(error: unknown): string {
-	if (error instanceof Error) {
-		const status = (error as Error & { status?: unknown }).status;
-		const statusCode = typeof status === "number" ? status : undefined;
-		if (statusCode !== undefined) {
-			return `OpenAI API error (${statusCode}): ${error.message}`;
-		}
-		return error.message;
-	}
-	try {
-		return JSON.stringify(error);
-	} catch {
-		return String(error);
-	}
+	return formatProviderError(normalizeProviderError(error), "OpenAI API error");
 }
 
 // OpenAI Responses-specific options
@@ -81,7 +86,7 @@ export interface OpenAIResponsesOptions extends StreamOptions {
 /**
  * Generate function for OpenAI Responses API
  */
-export const streamOpenAIResponses: StreamFunction<"openai-responses", OpenAIResponsesOptions> = (
+export const stream: StreamFunction<"openai-responses", OpenAIResponsesOptions> = (
 	model: Model<"openai-responses">,
 	context: Context,
 	options?: OpenAIResponsesOptions,
@@ -110,13 +115,10 @@ export const streamOpenAIResponses: StreamFunction<"openai-responses", OpenAIRes
 
 		try {
 			// Create OpenAI client
-			const apiKey = options?.apiKey;
-			if (!apiKey) {
-				throw new Error(`No API key for provider: ${model.provider}`);
-			}
+			const apiKey = getClientApiKey(model.provider, options?.apiKey, options?.headers);
 			const cacheRetention = resolveCacheRetention(options?.cacheRetention, options?.env);
 			const cacheSessionId = cacheRetention === "none" ? undefined : options?.sessionId;
-			const client = createClient(model, context, apiKey, options?.headers, cacheSessionId, options?.env);
+			const client = createClient(model, context, apiKey, options?.headers, cacheSessionId);
 			let params = buildParams(model, context, options);
 			const nextParams = await options?.onPayload?.(params, model);
 			if (nextParams !== undefined) {
@@ -162,44 +164,32 @@ export const streamOpenAIResponses: StreamFunction<"openai-responses", OpenAIRes
 	return stream;
 };
 
-export const streamSimpleOpenAIResponses: StreamFunction<"openai-responses", SimpleStreamOptions> = (
+export const streamSimple: StreamFunction<"openai-responses", SimpleStreamOptions> = (
 	model: Model<"openai-responses">,
 	context: Context,
 	options?: SimpleStreamOptions,
 ): AssistantMessageEventStream => {
-	const apiKey = options?.apiKey;
-	if (!apiKey) {
-		throw new Error(`No API key for provider: ${model.provider}`);
-	}
+	getClientApiKey(model.provider, options?.apiKey, options?.headers);
 
-	const base = buildBaseOptions(model, options, apiKey);
+	const base = buildBaseOptions(model, context, options, options?.apiKey);
 	const clampedReasoning = options?.reasoning ? clampThinkingLevel(model, options.reasoning) : undefined;
 	const reasoningEffort = clampedReasoning === "off" ? undefined : clampedReasoning;
 
-	return streamOpenAIResponses(model, context, {
+	return stream(model, context, {
 		...base,
 		reasoningEffort,
 	} satisfies OpenAIResponsesOptions);
 };
 
-export function register(): void {
-	registerApiProvider({
-		api: "openai-responses",
-		stream: streamOpenAIResponses,
-		streamSimple: streamSimpleOpenAIResponses,
-	});
-}
-
 function createClient(
 	model: Model<"openai-responses">,
 	context: Context,
 	apiKey: string,
-	optionsHeaders?: Record<string, string>,
+	optionsHeaders?: ProviderHeaders,
 	sessionId?: string,
-	env?: ProviderEnv,
 ) {
 	const compat = getCompat(model);
-	const headers = { ...model.headers };
+	const headers: ProviderHeaders = { ...model.headers };
 	if (model.provider === "github-copilot") {
 		const hasImages = hasCopilotVisionInput(context.messages);
 		const copilotHeaders = buildCopilotDynamicHeaders({
@@ -221,20 +211,11 @@ function createClient(
 		Object.assign(headers, optionsHeaders);
 	}
 
-	const defaultHeaders =
-		model.provider === "cloudflare-ai-gateway"
-			? {
-					...headers,
-					Authorization: headers.Authorization ?? null,
-					"cf-aig-authorization": `Bearer ${apiKey}`,
-				}
-			: headers;
-
 	return new OpenAI({
 		apiKey,
-		baseURL: isCloudflareProvider(model.provider) ? resolveCloudflareBaseUrl(model, env) : model.baseUrl,
+		baseURL: model.baseUrl,
 		dangerouslyAllowBrowser: true,
-		defaultHeaders,
+		defaultHeaders: headers,
 	});
 }
 
@@ -253,7 +234,7 @@ function buildParams(model: Model<"openai-responses">, context: Context, options
 	};
 
 	if (options?.maxTokens) {
-		params.max_output_tokens = options?.maxTokens;
+		params.max_output_tokens = Math.max(options.maxTokens, OPENAI_RESPONSES_MIN_OUTPUT_TOKENS);
 	}
 
 	if (options?.temperature !== undefined) {

packages/ai/src/api/openrouter-images.lazy.ts

@@ -0,0 +1,10 @@
+import type { ImagesModel, ProviderImages } from "../types.ts";
+
+export const openrouterImagesApi = (): ProviderImages => ({
+	generateImages: async (model, context, options) =>
+		(await import("./openrouter-images.ts")).generateImages(
+			model as ImagesModel<"openrouter-images">,
+			context,
+			options,
+		),
+});

packages/ai/src/api/openrouter-images.ts

@@ -6,7 +6,6 @@ import type {
 	ChatCompletionContentPartText,
 	ChatCompletionCreateParamsNonStreaming,
 } from "openai/resources/chat/completions.js";
-import { registerImagesApiProvider } from "../../images-api-registry.ts";
 import type {
 	AssistantImages,
 	ImageContent,
@@ -14,10 +13,12 @@ import type {
 	ImagesFunction,
 	ImagesModel,
 	ImagesOptions,
+	ProviderHeaders,
 	TextContent,
-} from "../../types.ts";
-import { headersToRecord } from "../../utils/headers.ts";
-import { sanitizeSurrogates } from "../../utils/sanitize-unicode.ts";
+} from "../types.ts";
+import { formatProviderError, normalizeProviderError } from "../utils/error-body.ts";
+import { headersToRecord, providerHeadersToRecord } from "../utils/headers.ts";
+import { sanitizeSurrogates } from "../utils/sanitize-unicode.ts";
 
 interface OpenRouterGeneratedImage {
 	image_url?: string | { url?: string };
@@ -35,7 +36,7 @@ type OpenRouterImageGenerationResponse = ChatCompletion & {
 	choices: OpenRouterImageGenerationChoice[];
 };
 
-export const generateImagesOpenRouter: ImagesFunction<"openrouter-images", ImagesOptions> = async (
+export const generateImages: ImagesFunction<"openrouter-images", ImagesOptions> = async (
 	model: ImagesModel<"openrouter-images">,
 	context: ImagesContext,
 	options?: ImagesOptions,
@@ -99,31 +100,21 @@ export const generateImagesOpenRouter: ImagesFunction<"openrouter-images", Image
 		return output;
 	} catch (error) {
 		output.stopReason = options?.signal?.aborted ? "aborted" : "error";
-		output.errorMessage = error instanceof Error ? error.message : JSON.stringify(error);
+		output.errorMessage = formatProviderError(normalizeProviderError(error));
 		return output;
 	}
 };
 
-export function register(): void {
-	registerImagesApiProvider({
-		api: "openrouter-images",
-		generateImages: generateImagesOpenRouter,
-	});
-}
-
 function createClient(
 	model: ImagesModel<"openrouter-images">,
 	apiKey: string,
-	optionsHeaders?: Record<string, string>,
+	optionsHeaders?: ProviderHeaders,
 ): OpenAI {
 	return new OpenAI({
 		apiKey,
 		baseURL: model.baseUrl,
 		dangerouslyAllowBrowser: true,
-		defaultHeaders: {
-			...model.headers,
-			...optionsHeaders,
-		},
+		defaultHeaders: providerHeadersToRecord({ ...model.headers, ...optionsHeaders }),
 	});
 }
 

packages/ai/src/api/simple-options.ts

@@ -1,9 +1,32 @@
-import type { Api, Model, SimpleStreamOptions, StreamOptions, ThinkingBudgets, ThinkingLevel } from "../types.ts";
+import type {
+	Api,
+	Context,
+	Model,
+	SimpleStreamOptions,
+	StreamOptions,
+	ThinkingBudgets,
+	ThinkingLevel,
+} from "../types.ts";
+import { estimateContextTokens } from "../utils/estimate.ts";
 
-export function buildBaseOptions(_model: Model<Api>, options?: SimpleStreamOptions, apiKey?: string): StreamOptions {
+const CONTEXT_SAFETY_TOKENS = 4096;
+const MIN_MAX_TOKENS = 1;
+
+export function clampMaxTokensToContext(model: Model<Api>, context: Context, maxTokens: number): number {
+	if (model.contextWindow <= 0) return Math.max(MIN_MAX_TOKENS, maxTokens);
+	const available = model.contextWindow - estimateContextTokens(context).tokens - CONTEXT_SAFETY_TOKENS;
+	return Math.min(maxTokens, Math.max(MIN_MAX_TOKENS, available));
+}
+
+export function buildBaseOptions(
+	model: Model<Api>,
+	context: Context,
+	options?: SimpleStreamOptions,
+	apiKey?: string,
+): StreamOptions {
 	return {
 		temperature: options?.temperature,
-		maxTokens: options?.maxTokens,
+		maxTokens: clampMaxTokensToContext(model, context, options?.maxTokens ?? model.maxTokens),
 		signal: options?.signal,
 		apiKey: apiKey || options?.apiKey,
 		transport: options?.transport,

packages/ai/src/api/transform-messages.ts

@@ -68,7 +68,10 @@ export function transformMessages<TApi extends Api>(
 ): Message[] {
 	// Build a map of original tool call IDs to normalized IDs
 	const toolCallIdMap = new Map<string, string>();
-	const imageAwareMessages = downgradeUnsupportedImages(messages, model);
+	// Normalize null/undefined content from untyped callers (custom tools, hand-built
+	// histories, old session files) so downstream code can rely on the type contract.
+	const normalizedMessages = messages.map((msg) => (msg.content == null ? { ...msg, content: [] } : msg));
+	const imageAwareMessages = downgradeUnsupportedImages(normalizedMessages, model);
 
 	// First pass: transform messages (unsupported image downgrade, thinking blocks, tool call ID normalization)
 	const transformed = imageAwareMessages.map((msg) => {

packages/ai/src/auth/context.ts

@@ -0,0 +1,45 @@
+import type { AuthContext } from "./types.ts";
+
+interface NodeFsModule {
+	access(path: string): Promise<void>;
+}
+
+interface NodeOsModule {
+	homedir(): string;
+}
+
+// Variable specifier so browser bundlers do not try to resolve node builtins.
+const importNodeModule = (specifier: string): Promise<unknown> => import(specifier);
+
+function getProcessEnv(): Record<string, string | undefined> | undefined {
+	const proc = (globalThis as { process?: { env?: Record<string, string | undefined> } }).process;
+	return proc?.env;
+}
+
+/**
+ * Default auth context: env vars from `process.env` (undefined in browsers),
+ * file existence via node:fs (always false in browsers).
+ */
+export function defaultProviderAuthContext(): AuthContext {
+	return {
+		async env(name: string): Promise<string | undefined> {
+			const value = getProcessEnv()?.[name];
+			return typeof value === "string" && value.trim().length > 0 ? value : undefined;
+		},
+
+		async fileExists(path: string): Promise<boolean> {
+			try {
+				const fs = (await importNodeModule("node:fs/promises")) as NodeFsModule;
+				let resolved = path;
+				if (resolved.startsWith("~")) {
+					const os = (await importNodeModule("node:os")) as NodeOsModule;
+					resolved = os.homedir() + resolved.slice(1);
+				}
+				await fs.access(resolved);
+				return true;
+			} catch {
+				return false;
+			}
+		},
+	};
+}

packages/ai/src/auth/credential-store.ts

@@ -0,0 +1,47 @@
+import type { Credential, CredentialStore } from "./types.ts";
+
+/**
+ * Default in-memory credential store. Apps inject persistent stores.
+ * Keyed by `Provider.id`, one credential per provider; see `CredentialStore`.
+ * Writes are serialized per provider through a promise chain.
+ */
+export class InMemoryCredentialStore implements CredentialStore {
+	private credentials = new Map<string, Credential>();
+	private chains = new Map<string, Promise<unknown>>();
+
+	/** Serialize tasks per provider id. */
+	private enqueue<T>(providerId: string, task: () => Promise<T>): Promise<T> {
+		const previous = this.chains.get(providerId) ?? Promise.resolve();
+		const next = (async () => {
+			await previous.catch(() => {});
+			return task();
+		})();
+		this.chains.set(
+			providerId,
+			next.catch(() => {}),
+		);
+		return next;
+	}
+
+	async read(providerId: string): Promise<Credential | undefined> {
+		return this.credentials.get(providerId);
+	}
+
+	modify(
+		providerId: string,
+		fn: (current: Credential | undefined) => Promise<Credential | undefined>,
+	): Promise<Credential | undefined> {
+		return this.enqueue(providerId, async () => {
+			const current = this.credentials.get(providerId);
+			const next = await fn(current);
+			if (next !== undefined) this.credentials.set(providerId, next);
+			return next ?? current;
+		});
+	}
+
+	delete(providerId: string): Promise<void> {
+		return this.enqueue(providerId, async () => {
+			this.credentials.delete(providerId);
+		});
+	}
+}

packages/ai/src/auth/helpers.ts

@@ -0,0 +1,46 @@
+import type { ApiKeyAuth, OAuthAuth } from "./types.ts";
+
+/**
+ * Standard api-key auth: a stored credential key wins, otherwise the first
+ * set env var resolves. Includes a `login` that prompts for the key.
+ * Providers with non-standard resolution (provider env, ambient files, IAM)
+ * write their own `ApiKeyAuth`.
+ */
+export function envApiKeyAuth(name: string, envVars: readonly string[]): ApiKeyAuth {
+	return {
+		name,
+		login: async (callbacks) => {
+			const key = await callbacks.prompt({ type: "secret", message: `Enter ${name}` });
+			return { type: "api_key", key };
+		},
+		resolve: async ({ ctx, credential }) => {
+			if (credential?.key) return { auth: { apiKey: credential.key }, source: "stored credential" };
+			for (const envVar of envVars) {
+				const value = await ctx.env(envVar);
+				if (value) return { auth: { apiKey: value }, source: envVar };
+			}
+			return undefined;
+		},
+	};
+}
+
+/**
+ * Wraps a dynamically imported `OAuthAuth` so provider definitions can
+ * advertise OAuth without importing the implementation. The flow loads on
+ * first `login`/`refresh`/`toAuth` call; callers keep Node-only flow code out
+ * of bundles by loading through a bundler-opaque dynamic import (variable
+ * specifier, see the bedrock lazy wrapper).
+ */
+export function lazyOAuth(input: { name: string; load: () => Promise<OAuthAuth> }): OAuthAuth {
+	let promise: Promise<OAuthAuth> | undefined;
+	const loaded = () => {
+		promise ??= input.load();
+		return promise;
+	};
+	return {
+		name: input.name,
+		login: async (callbacks) => (await loaded()).login(callbacks),
+		refresh: async (credential) => (await loaded()).refresh(credential),
+		toAuth: async (credential) => (await loaded()).toAuth(credential),
+	};
+}

packages/ai/src/auth/resolve.ts

@@ -0,0 +1,141 @@
+import type { Api, ImagesApi, ImagesModel, Model, ProviderEnv } from "../types.ts";
+import type {
+	ApiKeyAuth,
+	ApiKeyCredential,
+	AuthContext,
+	AuthResult,
+	Credential,
+	CredentialStore,
+	OAuthAuth,
+	OAuthCredential,
+	ProviderAuth,
+} from "./types.ts";
+
+export type ModelsErrorCode = "model_source" | "model_validation" | "provider" | "stream" | "auth" | "oauth";
+
+export interface AuthResolutionOverrides {
+	apiKey?: string;
+	env?: ProviderEnv;
+}
+
+export class ModelsError extends Error {
+	readonly code: ModelsErrorCode;
+
+	constructor(code: ModelsErrorCode, message: string, options?: { cause?: unknown }) {
+		super(message, options);
+		this.name = "ModelsError";
+		this.code = code;
+	}
+}
+
+/** Model shape auth resolution receives: chat or image-generation models. */
+export type AuthModel = Model<Api> | ImagesModel<ImagesApi>;
+
+/**
+ * Auth resolution shared by the `Models` and `ImagesModels` collections.
+ * A stored credential owns the provider: ambient/env is consulted only when
+ * nothing is stored. No silent env fallback after a failed refresh or for a
+ * credential type without a matching handler.
+ */
+export async function resolveProviderAuth(
+	provider: { id: string; auth: ProviderAuth },
+	model: AuthModel,
+	credentials: CredentialStore,
+	authContext: AuthContext,
+	overrides?: AuthResolutionOverrides,
+): Promise<AuthResult | undefined> {
+	const requestAuthContext = overrides?.env ? overlayEnvAuthContext(authContext, overrides.env) : authContext;
+
+	if (overrides?.apiKey !== undefined && provider.auth.apiKey) {
+		return resolveApiKey(requestAuthContext, provider.auth.apiKey, model, {
+			type: "api_key",
+			key: overrides.apiKey,
+			env: overrides.env,
+		});
+	}
+
+	const stored = await readCredential(credentials, provider.id);
+	if (stored) {
+		if (stored.type === "oauth" && provider.auth.oauth) {
+			return resolveStoredOAuth(credentials, provider.id, provider.auth.oauth, stored);
+		}
+		if (stored.type === "api_key" && provider.auth.apiKey) {
+			const credential = overrides?.env ? { ...stored, env: { ...stored.env, ...overrides.env } } : stored;
+			return resolveApiKey(requestAuthContext, provider.auth.apiKey, model, credential);
+		}
+		return undefined;
+	}
+
+	// Ambient (env vars, AWS profiles, ADC files).
+	return provider.auth.apiKey ? resolveApiKey(requestAuthContext, provider.auth.apiKey, model, undefined) : undefined;
+}
+
+function overlayEnvAuthContext(base: AuthContext, env: ProviderEnv): AuthContext {
+	return {
+		env: async (name) => env[name] || (await base.env(name)),
+		fileExists: (path) => base.fileExists(path),
+	};
+}
+
+/**
+ * OAuth resolution with double-checked locking (same pattern as today's
+ * AuthStorage): valid tokens cost zero locks; expired tokens lock, re-check
+ * expiry under the lock, refresh once globally, and persist the rotated
+ * credential before release.
+ */
+async function resolveStoredOAuth(
+	credentials: CredentialStore,
+	providerId: string,
+	oauth: OAuthAuth,
+	stored: OAuthCredential,
+): Promise<AuthResult | undefined> {
+	let credential = stored;
+
+	if (Date.now() >= credential.expires) {
+		// Optimistic check said expired; the authoritative check runs under the lock.
+		let post: Credential | undefined;
+		try {
+			post = await credentials.modify(providerId, async (current) => {
+				if (current?.type !== "oauth") return undefined; // logged out meanwhile
+				if (Date.now() < current.expires) return undefined; // another process/request refreshed
+				try {
+					return await oauth.refresh(current);
+				} catch (error) {
+					throw new ModelsError("oauth", `OAuth refresh failed for ${providerId}`, { cause: error });
+				}
+			});
+		} catch (error) {
+			if (error instanceof ModelsError) throw error;
+			throw new ModelsError("auth", `Credential store modify failed for ${providerId}`, { cause: error });
+		}
+		if (post?.type !== "oauth") return undefined; // logged out meanwhile
+		credential = post;
+	}
+
+	try {
+		return { auth: await oauth.toAuth(credential), source: "OAuth" };
+	} catch (error) {
+		throw new ModelsError("oauth", `OAuth auth derivation failed for ${providerId}`, { cause: error });
+	}
+}
+
+async function resolveApiKey(
+	authContext: AuthContext,
+	apiKey: ApiKeyAuth,
+	model: AuthModel,
+	credential: ApiKeyCredential | undefined,
+): Promise<AuthResult | undefined> {
+	try {
+		return await apiKey.resolve({ model, ctx: authContext, credential });
+	} catch (error) {
+		throw new ModelsError("auth", `API key auth failed for provider ${model.provider}`, { cause: error });
+	}
+}
+
+async function readCredential(credentials: CredentialStore, providerId: string): Promise<Credential | undefined> {
+	try {
+		return await credentials.read(providerId);
+	} catch (error) {
+		throw new ModelsError("auth", `Credential store read failed for ${providerId}`, { cause: error });
+	}
+}

packages/ai/src/auth/types.ts

@@ -0,0 +1,182 @@
+import type { Api, ImagesApi, ImagesModel, Model, ProviderEnv, ProviderHeaders } from "../types.ts";
+import type { OAuthCredentials } from "../utils/oauth/types.ts";
+
+/**
+ * Request auth for a single model request. If a value cannot be expressed as
+ * `apiKey`, `headers`, or `baseUrl`, it is provider config, not auth.
+ */
+export interface ModelAuth {
+	apiKey?: string;
+	headers?: ProviderHeaders;
+	baseUrl?: string;
+}
+
+/**
+ * Stored api-key credential. `env` holds provider-scoped environment/config
+ * values such as Cloudflare account/gateway ids.
+ */
+export interface ApiKeyCredential {
+	type: "api_key";
+	key?: string;
+	env?: ProviderEnv;
+}
+
+/** Stored OAuth credential (`access`, `refresh`, `expires` from OAuthCredentials). */
+export interface OAuthCredential extends OAuthCredentials {
+	type: "oauth";
+}
+
+/** One type-tagged credential per provider — the shape of today's auth.json. */
+export type Credential = ApiKeyCredential | OAuthCredential;
+
+/**
+ * App-owned credential storage, keyed by `Provider.id`, one credential per
+ * provider. `modify` is the only write path, so every mutation is a
+ * serialized read-modify-write; `Models.getAuth()` runs OAuth refresh inside
+ * `modify` so concurrent requests cannot double-refresh a rotated token. The
+ * app persists a credential after login via
+ * `modify(provider.id, async () => credential)`. Login/logout orchestration
+ * is app-owned.
+ *
+ * Error semantics: `read` resolves `undefined` for missing entries. Methods
+ * reject only on storage failure; `Models` wraps such rejections in
+ * `ModelsError` with code "auth". Best-effort stores that serve an in-memory
+ * view and record persistence errors internally (like coding-agent's
+ * AuthStorage) are valid implementations.
+ */
+export interface CredentialStore {
+	/**
+	 * Read the stored credential, possibly expired. Display/status use;
+	 * resolved request auth comes from `Models.getAuth()`.
+	 */
+	read(providerId: string): Promise<Credential | undefined>;
+
+	/**
+	 * Serialized write — the only write path. `fn` sees the current credential
+	 * because correct writes (refresh, login-during-refresh) depend on it;
+	 * return the new credential, or undefined to leave the entry unchanged.
+	 * Mutual exclusion per provider id, cross-process too where the backing
+	 * store supports it (e.g. a file lock). Resolves with the post-write
+	 * credential. Rejections from `fn` propagate.
+	 */
+	modify(
+		providerId: string,
+		fn: (current: Credential | undefined) => Promise<Credential | undefined>,
+	): Promise<Credential | undefined>;
+
+	/** Remove a credential (logout). Implementations serialize this against `modify`. */
+	delete(providerId: string): Promise<void>;
+}
+
+/** Environment access for auth resolution. Injectable for tests and browsers. */
+export interface AuthContext {
+	env(name: string): Promise<string | undefined>;
+	/** Check whether a file exists. Supports a leading `~`. Always false in browsers. */
+	fileExists(path: string): Promise<boolean>;
+}
+
+/** Result of resolving auth for a model. */
+export interface AuthResult {
+	auth: ModelAuth;
+	/** Provider-scoped environment/config values resolved from credentials and ambient context. */
+	env?: ProviderEnv;
+	/** Human-readable label for status UI: "ANTHROPIC_API_KEY", "OAuth", "~/.aws/credentials". */
+	source?: string;
+}
+
+/**
+ * Prompt shown to the user during login. `signal` lets the flow cancel a
+ * pending prompt when an out-of-band event resolves the step, e.g. a
+ * `manual_code` prompt raced against a callback server, aborted when the
+ * callback wins.
+ */
+export type AuthPrompt = { signal?: AbortSignal } & (
+	| { type: "text"; message: string; placeholder?: string }
+	| { type: "secret"; message: string; placeholder?: string }
+	| { type: "select"; message: string; options: readonly { id: string; label: string; description?: string }[] }
+	| { type: "manual_code"; message: string; placeholder?: string }
+);
+
+export type AuthEvent =
+	| { type: "auth_url"; url: string; instructions?: string }
+	| {
+			type: "device_code";
+			userCode: string;
+			verificationUri: string;
+			intervalSeconds?: number;
+			expiresInSeconds?: number;
+	  }
+	| { type: "progress"; message: string };
+
+/**
+ * Login interaction callbacks serving both api-key and OAuth flows.
+ *
+ * `prompt()` returns the entered/selected string (`select` returns the option
+ * id). Rejects on cancel/abort. `signal` aborts the whole login flow;
+ * per-prompt cancellation uses `AuthPrompt.signal`.
+ */
+export interface AuthLoginCallbacks {
+	signal?: AbortSignal;
+
+	prompt(prompt: AuthPrompt): Promise<string>;
+	notify(event: AuthEvent): void;
+}
+
+/**
+ * Api-key auth: stored key/provider env plus ambient sources (env vars, AWS
+ * profiles, ADC files). Ambient-only providers omit `login`.
+ */
+export interface ApiKeyAuth {
+	/** Display name, e.g. "Anthropic API key". */
+	name: string;
+
+	/** Interactive setup (prompt for key/provider env). Absent = ambient-only. */
+	login?(callbacks: AuthLoginCallbacks): Promise<ApiKeyCredential>;
+
+	/**
+	 * Resolve auth from the stored credential and/or ambient sources, merging
+	 * per field (`credential.key ?? env("...")`, `credential.env?.NAME ?? env("...")`).
+	 * undefined = not configured. Receives the chat or image-generation model
+	 * the request is for (both carry `provider` and `baseUrl`).
+	 */
+	resolve(input: {
+		model: Model<Api> | ImagesModel<ImagesApi>;
+		ctx: AuthContext;
+		credential?: ApiKeyCredential;
+	}): Promise<AuthResult | undefined>;
+}
+
+/**
+ * OAuth auth. The `refresh`/`toAuth` split lets `Models` own the locked
+ * refresh pattern: `refresh` produces a credential, `toAuth` derives request
+ * auth from whatever credential ends up stored.
+ */
+export interface OAuthAuth {
+	/** Display name, e.g. "Anthropic (Claude Pro/Max)". */
+	name: string;
+
+	login(callbacks: AuthLoginCallbacks): Promise<OAuthCredential>;
+
+	/**
+	 * Exchange the refresh token. Network call; throws on failure
+	 * (invalid_grant etc.). `Models` runs this under the store lock.
+	 */
+	refresh(credential: OAuthCredential): Promise<OAuthCredential>;
+
+	/**
+	 * Side-effect-free derivation of request auth from a valid credential.
+	 * Covers per-credential baseUrl (GitHub Copilot). Async so lazy wrappers
+	 * can load the implementation on first use.
+	 */
+	toAuth(credential: OAuthCredential): Promise<ModelAuth>;
+}
+
+/**
+ * Provider auth. At least one of `apiKey`/`oauth` must be present: even
+ * ambient-credential providers and keyless local servers provide `apiKey`
+ * auth whose `resolve()` reports whether the provider is configured.
+ */
+export interface ProviderAuth {
+	apiKey?: ApiKeyAuth;
+	oauth?: OAuthAuth;
+}

packages/ai/src/base.ts

@@ -1,45 +0,0 @@
-export type { Static, TSchema } from "typebox";
-export { Type } from "typebox";
-
-export * from "./api-registry.ts";
-export * from "./env-api-keys.ts";
-export * from "./image-models.ts";
-export * from "./images.ts";
-export * from "./images-api-registry.ts";
-export * from "./models.ts";
-export type { BedrockOptions, BedrockThinkingDisplay } from "./providers/amazon-bedrock.ts";
-export type { AnthropicEffort, AnthropicOptions, AnthropicThinkingDisplay } from "./providers/anthropic.ts";
-export type { AzureOpenAIResponsesOptions } from "./providers/azure-openai-responses.ts";
-export * from "./providers/faux.ts";
-export type { GoogleOptions } from "./providers/google.ts";
-export type { GoogleThinkingLevel } from "./providers/google-shared.ts";
-export type { GoogleVertexOptions } from "./providers/google-vertex.ts";
-export type { MistralOptions } from "./providers/mistral.ts";
-export type {
-	OpenAICodexResponsesOptions,
-	OpenAICodexWebSocketDebugStats,
-} from "./providers/openai-codex-responses.ts";
-export type { OpenAICompletionsOptions } from "./providers/openai-completions.ts";
-export type { OpenAIResponsesOptions } from "./providers/openai-responses.ts";
-export * from "./session-resources.ts";
-export * from "./stream.ts";
-export * from "./types.ts";
-export * from "./utils/diagnostics.ts";
-export * from "./utils/event-stream.ts";
-export * from "./utils/json-parse.ts";
-export type {
-	OAuthAuthInfo,
-	OAuthCredentials,
-	OAuthDeviceCodeInfo,
-	OAuthLoginCallbacks,
-	OAuthPrompt,
-	OAuthProvider,
-	OAuthProviderId,
-	OAuthProviderInfo,
-	OAuthProviderInterface,
-	OAuthSelectOption,
-	OAuthSelectPrompt,
-} from "./utils/oauth/types.ts";
-export * from "./utils/overflow.ts";
-export * from "./utils/typebox-helpers.ts";
-export * from "./utils/validation.ts";

packages/ai/src/bedrock-provider.ts

@@ -1,8 +1,6 @@
-import { register, streamBedrock, streamSimpleBedrock } from "./providers/amazon-bedrock.ts";
-
-export { register };
+import { stream, streamSimple } from "./api/bedrock-converse-stream.ts";
 
 export const bedrockProviderModule = {
-	streamBedrock,
-	streamSimpleBedrock,
+	stream,
+	streamSimple,
 };

packages/ai/src/compat.ts

@@ -0,0 +1,277 @@
+/**
+ * Temporary compatibility entrypoint preserving the old global pi-ai API
+ * surface: api-dispatch `stream()`/`complete()` with env API key injection,
+ * the api-registry, generated catalog reads (`getModel`/`getModels`/
+ * `getProviders`), per-API lazy stream wrappers, and image generation.
+ *
+ * Existing apps switch imports from "@earendil-works/pi-ai" to
+ * "@earendil-works/pi-ai/compat" unchanged; new code uses `createModels()`
+ * and the provider factories. This module is deleted with the coding-agent
+ * ModelManager migration.
+ */
+
+export * from "./api/anthropic-messages.lazy.ts";
+export * from "./api/azure-openai-responses.lazy.ts";
+export * from "./api/bedrock-converse-stream.lazy.ts";
+export * from "./api/google-generative-ai.lazy.ts";
+export * from "./api/google-vertex.lazy.ts";
+export * from "./api/mistral-conversations.lazy.ts";
+export * from "./api/openai-codex-responses.lazy.ts";
+export * from "./api/openai-completions.lazy.ts";
+export * from "./api/openai-responses.lazy.ts";
+export * from "./env-api-keys.ts";
+export * from "./image-models.ts";
+export * from "./images.ts";
+export * from "./images-api-registry.ts";
+export * from "./index.ts";
+export * from "./legacy-api-aliases.ts";
+export * from "./providers/images/register-builtins.ts";
+
+import { anthropicMessagesApi } from "./api/anthropic-messages.lazy.ts";
+import { azureOpenAIResponsesApi } from "./api/azure-openai-responses.lazy.ts";
+import { bedrockConverseStreamApi } from "./api/bedrock-converse-stream.lazy.ts";
+import { googleGenerativeAIApi } from "./api/google-generative-ai.lazy.ts";
+import { googleVertexApi } from "./api/google-vertex.lazy.ts";
+import { mistralConversationsApi } from "./api/mistral-conversations.lazy.ts";
+import { openAICodexResponsesApi } from "./api/openai-codex-responses.lazy.ts";
+import { openAICompletionsApi } from "./api/openai-completions.lazy.ts";
+import { openAIResponsesApi } from "./api/openai-responses.lazy.ts";
+import { getEnvApiKey } from "./env-api-keys.ts";
+import { builtinModels, getBuiltinModel, getBuiltinModels, getBuiltinProviders } from "./providers/all.ts";
+import { createFauxCore, type FauxProviderRegistration, type RegisterFauxProviderOptions } from "./providers/faux.ts";
+import type {
+	Api,
+	ApiStreamOptions,
+	AssistantMessage,
+	AssistantMessageEventStream,
+	Context,
+	Model,
+	ProviderStreamOptions,
+	ProviderStreams,
+	SimpleStreamOptions,
+	StreamFunction,
+	StreamOptions,
+} from "./types.ts";
+
+/** @deprecated Static catalog read. Use `getBuiltinModel` from "@earendil-works/pi-ai/providers/all" or `Models.getModel()`. */
+export const getModel = getBuiltinModel;
+
+/** @deprecated Static catalog read. Use `getBuiltinModels` from "@earendil-works/pi-ai/providers/all" or `Models.getModels()`. */
+export const getModels = getBuiltinModels;
+
+/** @deprecated Static catalog read. Use `getBuiltinProviders` from "@earendil-works/pi-ai/providers/all" or `Models.getProviders()`. */
+export const getProviders = getBuiltinProviders;
+
+export type ApiStreamFunction = (
+	model: Model<Api>,
+	context: Context,
+	options?: StreamOptions,
+) => AssistantMessageEventStream;
+
+export type ApiStreamSimpleFunction = (
+	model: Model<Api>,
+	context: Context,
+	options?: SimpleStreamOptions,
+) => AssistantMessageEventStream;
+
+export interface ApiProvider<TApi extends Api = Api, TOptions extends StreamOptions = StreamOptions> {
+	api: TApi;
+	stream: StreamFunction<TApi, TOptions>;
+	streamSimple: StreamFunction<TApi, SimpleStreamOptions>;
+}
+
+interface ApiProviderInternal {
+	api: Api;
+	stream: ApiStreamFunction;
+	streamSimple: ApiStreamSimpleFunction;
+}
+
+type RegisteredApiProvider = {
+	provider: ApiProviderInternal;
+	sourceId?: string;
+};
+
+const apiProviderRegistry = new Map<string, RegisteredApiProvider>();
+
+function wrapStream<TApi extends Api, TOptions extends StreamOptions>(
+	api: TApi,
+	stream: StreamFunction<TApi, TOptions>,
+): ApiStreamFunction {
+	return (model, context, options) => {
+		if (model.api !== api) {
+			throw new Error(`Mismatched api: ${model.api} expected ${api}`);
+		}
+		return stream(model as Model<TApi>, context, options as TOptions);
+	};
+}
+
+function wrapStreamSimple<TApi extends Api>(
+	api: TApi,
+	streamSimple: StreamFunction<TApi, SimpleStreamOptions>,
+): ApiStreamSimpleFunction {
+	return (model, context, options) => {
+		if (model.api !== api) {
+			throw new Error(`Mismatched api: ${model.api} expected ${api}`);
+		}
+		return streamSimple(model as Model<TApi>, context, options);
+	};
+}
+
+export function registerApiProvider<TApi extends Api, TOptions extends StreamOptions>(
+	provider: ApiProvider<TApi, TOptions>,
+	sourceId?: string,
+): void {
+	apiProviderRegistry.set(provider.api, {
+		provider: {
+			api: provider.api,
+			stream: wrapStream(provider.api, provider.stream),
+			streamSimple: wrapStreamSimple(provider.api, provider.streamSimple),
+		},
+		sourceId,
+	});
+}
+
+export function getApiProvider(api: Api): ApiProviderInternal | undefined {
+	return apiProviderRegistry.get(api)?.provider;
+}
+
+export function getApiProviders(): ApiProviderInternal[] {
+	return Array.from(apiProviderRegistry.values(), (entry) => entry.provider);
+}
+
+export function unregisterApiProviders(sourceId: string): void {
+	for (const [api, entry] of apiProviderRegistry.entries()) {
+		if (entry.sourceId === sourceId) {
+			apiProviderRegistry.delete(api);
+		}
+	}
+}
+
+function clearApiProviders(): void {
+	apiProviderRegistry.clear();
+}
+
+export function registerFauxProvider(options: RegisterFauxProviderOptions = {}): FauxProviderRegistration {
+	const core = createFauxCore(options);
+	const sourceId = `faux-provider-${Math.random().toString(36).slice(2, 10)}`;
+	registerApiProvider({ api: core.api, stream: core.stream, streamSimple: core.streamSimple }, sourceId);
+	return {
+		api: core.api,
+		models: core.models,
+		getModel: core.getModel,
+		state: core.state,
+		setResponses: core.setResponses,
+		appendResponses: core.appendResponses,
+		getPendingResponseCount: core.getPendingResponseCount,
+		unregister() {
+			unregisterApiProviders(sourceId);
+		},
+	};
+}
+
+const BUILTIN_APIS: [Api, ProviderStreams][] = [
+	["anthropic-messages", anthropicMessagesApi()],
+	["openai-completions", openAICompletionsApi()],
+	["openai-responses", openAIResponsesApi()],
+	["openai-codex-responses", openAICodexResponsesApi()],
+	["azure-openai-responses", azureOpenAIResponsesApi()],
+	["google-generative-ai", googleGenerativeAIApi()],
+	["google-vertex", googleVertexApi()],
+	["mistral-conversations", mistralConversationsApi()],
+	["bedrock-converse-stream", bedrockConverseStreamApi()],
+];
+
+const builtinApiProviderInstances = new Map<Api, ReturnType<typeof getApiProvider>>();
+
+/**
+ * Registers the builtin API implementations into the api-registry without
+ * clobbering existing entries: compat may load after a test or extension has
+ * already registered an override for a builtin api id.
+ */
+export function registerBuiltInApiProviders(): void {
+	for (const [api, streams] of BUILTIN_APIS) {
+		if (!getApiProvider(api)) {
+			registerApiProvider({ api, stream: streams.stream, streamSimple: streams.streamSimple });
+		}
+		builtinApiProviderInstances.set(api, getApiProvider(api));
+	}
+}
+
+export function resetApiProviders(): void {
+	clearApiProviders();
+	builtinApiProviderInstances.clear();
+	registerBuiltInApiProviders();
+}
+
+registerBuiltInApiProviders();
+
+const compatModels = builtinModels();
+
+function hasExplicitApiKey(apiKey: string | undefined): apiKey is string {
+	return typeof apiKey === "string" && apiKey.trim().length > 0;
+}
+
+function withEnvApiKey<TOptions extends StreamOptions>(
+	model: Model<Api>,
+	options: TOptions | undefined,
+): TOptions | undefined {
+	if (hasExplicitApiKey(options?.apiKey)) return options;
+	const apiKey = getEnvApiKey(model.provider, options?.env);
+	if (!apiKey) return options;
+	return { ...options, apiKey } as TOptions;
+}
+
+function shouldUseBuiltinModels(model: Model<Api>): boolean {
+	const builtin = compatModels.getModel(model.provider, model.id);
+	return builtin?.api === model.api && getApiProvider(model.api) === builtinApiProviderInstances.get(model.api);
+}
+
+function resolveApiProvider(api: Api) {
+	const provider = getApiProvider(api);
+	if (!provider) {
+		throw new Error(`No API provider registered for api: ${api}`);
+	}
+	return provider;
+}
+
+export function stream<TApi extends Api>(
+	model: Model<TApi>,
+	context: Context,
+	options?: ProviderStreamOptions,
+): AssistantMessageEventStream {
+	if (shouldUseBuiltinModels(model)) {
+		return compatModels.stream(model, context, options as ApiStreamOptions<TApi> | undefined);
+	}
+	const provider = resolveApiProvider(model.api);
+	return provider.stream(model, context, withEnvApiKey(model, options) as StreamOptions);
+}
+
+export async function complete<TApi extends Api>(
+	model: Model<TApi>,
+	context: Context,
+	options?: ProviderStreamOptions,
+): Promise<AssistantMessage> {
+	const s = stream(model, context, options);
+	return s.result();
+}
+
+export function streamSimple<TApi extends Api>(
+	model: Model<TApi>,
+	context: Context,
+	options?: SimpleStreamOptions,
+): AssistantMessageEventStream {
+	if (shouldUseBuiltinModels(model)) {
+		return compatModels.streamSimple(model, context, options);
+	}
+	const provider = resolveApiProvider(model.api);
+	return provider.streamSimple(model, context, withEnvApiKey(model, options));
+}
+
+export async function completeSimple<TApi extends Api>(
+	model: Model<TApi>,
+	context: Context,
+	options?: SimpleStreamOptions,
+): Promise<AssistantMessage> {
+	const s = streamSimple(model, context, options);
+	return s.result();
+}

packages/ai/src/image-models.generated.ts

@@ -155,6 +155,21 @@ export const IMAGE_MODELS = {
 				cacheWrite: 0,
 			},
 		} satisfies ImagesModel<"openrouter-images">,
+		"google/gemini-3.1-flash-lite-image": {
+			id: "google/gemini-3.1-flash-lite-image",
+			name: "Google: Nano Banana 2 Lite (Gemini 3.1 Flash Lite Image)",
+			api: "openrouter-images",
+			provider: "openrouter",
+			baseUrl: "https://openrouter.ai/api/v1",
+			input: ["image", "text"],
+			output: ["image", "text"],
+			cost: {
+				input: 0.25,
+				output: 1.5,
+				cacheRead: 0,
+				cacheWrite: 0,
+			},
+		} satisfies ImagesModel<"openrouter-images">,
 		"microsoft/mai-image-2.5": {
 			id: "microsoft/mai-image-2.5",
 			name: "Microsoft: MAI-Image-2.5",
@@ -215,6 +230,51 @@ export const IMAGE_MODELS = {
 				cacheWrite: 0,
 			},
 		} satisfies ImagesModel<"openrouter-images">,
+		"openai/gpt-image-1": {
+			id: "openai/gpt-image-1",
+			name: "OpenAI: GPT Image 1",
+			api: "openrouter-images",
+			provider: "openrouter",
+			baseUrl: "https://openrouter.ai/api/v1",
+			input: ["text", "image"],
+			output: ["image"],
+			cost: {
+				input: 10,
+				output: 10,
+				cacheRead: 1.25,
+				cacheWrite: 0,
+			},
+		} satisfies ImagesModel<"openrouter-images">,
+		"openai/gpt-image-1-mini": {
+			id: "openai/gpt-image-1-mini",
+			name: "OpenAI: GPT Image 1 Mini",
+			api: "openrouter-images",
+			provider: "openrouter",
+			baseUrl: "https://openrouter.ai/api/v1",
+			input: ["text", "image"],
+			output: ["image"],
+			cost: {
+				input: 2.5,
+				output: 2.5,
+				cacheRead: 0.25,
+				cacheWrite: 0,
+			},
+		} satisfies ImagesModel<"openrouter-images">,
+		"openai/gpt-image-2": {
+			id: "openai/gpt-image-2",
+			name: "OpenAI: GPT Image 2",
+			api: "openrouter-images",
+			provider: "openrouter",
+			baseUrl: "https://openrouter.ai/api/v1",
+			input: ["text", "image"],
+			output: ["image"],
+			cost: {
+				input: 8,
+				output: 8,
+				cacheRead: 2,
+				cacheWrite: 0,
+			},
+		} satisfies ImagesModel<"openrouter-images">,
 		"openrouter/auto": {
 			id: "openrouter/auto",
 			name: "Auto Router",
@@ -410,36 +470,6 @@ export const IMAGE_MODELS = {
 				cacheWrite: 0,
 			},
 		} satisfies ImagesModel<"openrouter-images">,
-		"sourceful/riverflow-v2-fast-preview": {
-			id: "sourceful/riverflow-v2-fast-preview",
-			name: "Sourceful: Riverflow V2 Fast Preview",
-			api: "openrouter-images",
-			provider: "openrouter",
-			baseUrl: "https://openrouter.ai/api/v1",
-			input: ["text", "image"],
-			output: ["image"],
-			cost: {
-				input: 0,
-				output: 0,
-				cacheRead: 0,
-				cacheWrite: 0,
-			},
-		} satisfies ImagesModel<"openrouter-images">,
-		"sourceful/riverflow-v2-max-preview": {
-			id: "sourceful/riverflow-v2-max-preview",
-			name: "Sourceful: Riverflow V2 Max Preview",
-			api: "openrouter-images",
-			provider: "openrouter",
-			baseUrl: "https://openrouter.ai/api/v1",
-			input: ["text", "image"],
-			output: ["image"],
-			cost: {
-				input: 0,
-				output: 0,
-				cacheRead: 0,
-				cacheWrite: 0,
-			},
-		} satisfies ImagesModel<"openrouter-images">,
 		"sourceful/riverflow-v2-pro": {
 			id: "sourceful/riverflow-v2-pro",
 			name: "Sourceful: Riverflow V2 Pro",
@@ -455,21 +485,6 @@ export const IMAGE_MODELS = {
 				cacheWrite: 0,
 			},
 		} satisfies ImagesModel<"openrouter-images">,
-		"sourceful/riverflow-v2-standard-preview": {
-			id: "sourceful/riverflow-v2-standard-preview",
-			name: "Sourceful: Riverflow V2 Standard Preview",
-			api: "openrouter-images",
-			provider: "openrouter",
-			baseUrl: "https://openrouter.ai/api/v1",
-			input: ["text", "image"],
-			output: ["image"],
-			cost: {
-				input: 0,
-				output: 0,
-				cacheRead: 0,
-				cacheWrite: 0,
-			},
-		} satisfies ImagesModel<"openrouter-images">,
 		"sourceful/riverflow-v2.5-fast": {
 			id: "sourceful/riverflow-v2.5-fast",
 			name: "Sourceful: Riverflow V2.5 Fast",

packages/ai/src/images-api-registry.ts

@@ -51,7 +51,3 @@ export function registerImagesApiProvider<TApi extends ImagesApi, TOptions exten
 export function getImagesApiProvider(api: ImagesApi): ImagesApiProviderInternal | undefined {
 	return imagesApiProviderRegistry.get(api)?.provider;
 }
-
-export function clearImagesApiProviders(): void {
-	imagesApiProviderRegistry.clear();
-}

packages/ai/src/images-models.ts

@@ -0,0 +1,267 @@
+import { defaultProviderAuthContext as defaultAuthContext } from "./auth/context.ts";
+import { InMemoryCredentialStore } from "./auth/credential-store.ts";
+import { ModelsError, resolveProviderAuth } from "./auth/resolve.ts";
+import type { AuthContext, AuthResult, CredentialStore, ProviderAuth } from "./auth/types.ts";
+import type { CreateModelsOptions } from "./models.ts";
+import type { AssistantImages, ImagesApi, ImagesContext, ImagesModel, ImagesOptions, ProviderImages } from "./types.ts";
+
+/**
+ * An image-generation provider: the image-side counterpart of `Provider`.
+ * Owns id/name metadata, auth, model listing, and generation behavior.
+ */
+export interface ImagesProvider {
+	readonly id: string;
+	readonly name: string;
+
+	/**
+	 * Required: at least one of `apiKey`/`oauth`. Same semantics as chat
+	 * providers; `ImagesModels.getAuth()` returns undefined when the provider
+	 * is unconfigured.
+	 */
+	readonly auth: ProviderAuth;
+
+	/**
+	 * Current known models, sync. Static providers return their catalog;
+	 * dynamic providers return the list as of the last `refreshModels()`
+	 * (empty before the first). Must not throw; `ImagesModels` treats a
+	 * throwing implementation as having no models.
+	 */
+	getModels(): readonly ImagesModel<ImagesApi>[];
+
+	/**
+	 * Dynamic providers only: fetch and update the model list. May reject
+	 * (network); on rejection the model list stays at its last-known state
+	 * and a later call retries.
+	 */
+	refreshModels?(): Promise<void>;
+
+	generateImages(
+		model: ImagesModel<ImagesApi>,
+		context: ImagesContext,
+		options?: ImagesOptions,
+	): Promise<AssistantImages>;
+}
+
+/**
+ * Runtime collection of image-generation providers plus auth application and
+ * generation convenience: the image-side counterpart of `Models`.
+ */
+export interface ImagesModels {
+	getProviders(): readonly ImagesProvider[];
+	getProvider(id: string): ImagesProvider | undefined;
+
+	/**
+	 * Sync read of last-known models from one provider or all providers.
+	 * Best-effort: a provider whose `getModels()` throws yields no models.
+	 */
+	getModels(provider?: string): readonly ImagesModel<ImagesApi>[];
+
+	/** Sync runtime model lookup against last-known lists. */
+	getModel(provider: string, id: string): ImagesModel<ImagesApi> | undefined;
+
+	/**
+	 * Ask dynamic providers to re-fetch their model lists. With a provider id,
+	 * rejects with `ModelsError` ("model_source") on that provider's fetch
+	 * failure; without one, refreshes all providers concurrently best-effort.
+	 * Static providers (no `refreshModels`) are no-ops.
+	 */
+	refresh(provider?: string): Promise<void>;
+
+	/**
+	 * Resolve request auth for an image model. Same contract as
+	 * `Models.getAuth()`: undefined when unknown/unconfigured, rejects with
+	 * `ModelsError` ("oauth"/"auth") on real failures.
+	 */
+	getAuth(model: ImagesModel<ImagesApi>): Promise<AuthResult | undefined>;
+
+	/**
+	 * Generate images through the owning provider with auth resolved and
+	 * merged (explicit options win per field). Never rejects; failures are
+	 * returned as an `AssistantImages` with `stopReason: "error"`.
+	 */
+	generateImages(
+		model: ImagesModel<ImagesApi>,
+		context: ImagesContext,
+		options?: ImagesOptions,
+	): Promise<AssistantImages>;
+}
+
+export interface MutableImagesModels extends ImagesModels {
+	/** Upsert/replace by provider.id. Provider ids are unique. */
+	setProvider(provider: ImagesProvider): void;
+	deleteProvider(id: string): void;
+	clearProviders(): void;
+}
+
+class ImagesModelsImpl implements MutableImagesModels {
+	private providers = new Map<string, ImagesProvider>();
+	private credentials: CredentialStore;
+	private authContext: AuthContext;
+
+	constructor(options?: CreateModelsOptions) {
+		this.credentials = options?.credentials ?? new InMemoryCredentialStore();
+		this.authContext = options?.authContext ?? defaultAuthContext();
+	}
+
+	setProvider(provider: ImagesProvider): void {
+		this.providers.set(provider.id, provider);
+	}
+
+	deleteProvider(id: string): void {
+		this.providers.delete(id);
+	}
+
+	clearProviders(): void {
+		this.providers.clear();
+	}
+
+	getProviders(): readonly ImagesProvider[] {
+		return Array.from(this.providers.values());
+	}
+
+	getProvider(id: string): ImagesProvider | undefined {
+		return this.providers.get(id);
+	}
+
+	getModels(provider?: string): readonly ImagesModel<ImagesApi>[] {
+		if (provider !== undefined) {
+			const entry = this.providers.get(provider);
+			if (!entry) return [];
+			try {
+				return entry.getModels();
+			} catch {
+				return [];
+			}
+		}
+
+		const models: ImagesModel<ImagesApi>[] = [];
+		for (const entry of this.providers.values()) {
+			try {
+				models.push(...entry.getModels());
+			} catch {
+				// Best-effort: ill-behaved providers yield no models.
+			}
+		}
+		return models;
+	}
+
+	getModel(provider: string, id: string): ImagesModel<ImagesApi> | undefined {
+		return this.getModels(provider).find((model) => model.id === id);
+	}
+
+	async refresh(provider?: string): Promise<void> {
+		if (provider !== undefined) {
+			const entry = this.providers.get(provider);
+			if (!entry?.refreshModels) return;
+			try {
+				await entry.refreshModels();
+			} catch (error) {
+				if (error instanceof ModelsError) throw error;
+				throw new ModelsError("model_source", `Model refresh failed for ${provider}`, { cause: error });
+			}
+			return;
+		}
+
+		// Cannot reject: the async mapper turns even sync throws from ill-behaved
+		// providers into rejections, and allSettled captures all of them.
+		await Promise.allSettled(Array.from(this.providers.values(), async (entry) => entry.refreshModels?.()));
+	}
+
+	async getAuth(model: ImagesModel<ImagesApi>): Promise<AuthResult | undefined> {
+		const provider = this.providers.get(model.provider);
+		if (!provider) return undefined;
+		return resolveProviderAuth(provider, model, this.credentials, this.authContext);
+	}
+
+	async generateImages(
+		model: ImagesModel<ImagesApi>,
+		context: ImagesContext,
+		options?: ImagesOptions,
+	): Promise<AssistantImages> {
+		try {
+			const provider = this.providers.get(model.provider);
+			if (!provider) {
+				throw new ModelsError("provider", `Unknown provider: ${model.provider}`);
+			}
+
+			const resolution = await resolveProviderAuth(provider, model, this.credentials, this.authContext, {
+				apiKey: options?.apiKey,
+				env: options?.env,
+			});
+			const auth = resolution?.auth;
+			if (!auth) {
+				return provider.generateImages(model, context, options);
+			}
+
+			const requestModel = auth.baseUrl ? { ...model, baseUrl: auth.baseUrl } : model;
+
+			// Explicit request options win per-field; headers/env merge per key.
+			const apiKey = options?.apiKey ?? auth.apiKey;
+			const headers = auth.headers || options?.headers ? { ...auth.headers, ...options?.headers } : undefined;
+			const env =
+				resolution.env || options?.env ? { ...(resolution.env ?? {}), ...(options?.env ?? {}) } : undefined;
+
+			return await provider.generateImages(requestModel, context, { ...options, apiKey, headers, env });
+		} catch (error) {
+			return {
+				api: model.api,
+				provider: model.provider,
+				model: model.id,
+				output: [],
+				stopReason: "error",
+				errorMessage: error instanceof Error ? error.message : String(error),
+				timestamp: Date.now(),
+			};
+		}
+	}
+}
+
+export function createImagesModels(options?: CreateModelsOptions): MutableImagesModels {
+	return new ImagesModelsImpl(options);
+}
+
+export interface CreateImagesProviderOptions {
+	id: string;
+	/** Display name. Default: `id`. */
+	name?: string;
+	/** Required — every provider has auth semantics, even ambient/keyless ones. */
+	auth: ProviderAuth;
+	/** Initial model list (empty for purely dynamic providers). */
+	models: readonly ImagesModel<ImagesApi>[];
+	/**
+	 * Dynamic providers: fetch the current list. Stored on success; concurrent
+	 * calls share one in-flight fetch. May reject: the stored list then stays
+	 * at its last-known state, the rejection propagates to the caller of
+	 * `refreshModels()` (wrapped as ModelsError "model_source" by
+	 * `ImagesModels.refresh(provider)`), and a later call retries.
+	 */
+	refreshModels?: () => Promise<readonly ImagesModel<ImagesApi>[]>;
+	api: ProviderImages;
+}
+
+/** Builds an image-generation provider from parts. */
+export function createImagesProvider(input: CreateImagesProviderOptions): ImagesProvider {
+	let models = input.models;
+	let inflightRefresh: Promise<void> | undefined;
+	const refreshModels = input.refreshModels;
+
+	return {
+		id: input.id,
+		name: input.name ?? input.id,
+		auth: input.auth,
+		getModels: () => models,
+		refreshModels: refreshModels
+			? () => {
+					inflightRefresh ??= (async () => {
+						try {
+							models = await refreshModels();
+						} finally {
+							inflightRefresh = undefined;
+						}
+					})();
+					return inflightRefresh;
+				}
+			: undefined,
+		generateImages: (model, context, options) => input.api.generateImages(model, context, options),
+	};
+}

packages/ai/src/images.ts

@@ -1,3 +1,5 @@
+import "./providers/images/register-builtins.ts";
+
 import { getImagesApiProvider } from "./images-api-registry.ts";
 import type { AssistantImages, ImagesApi, ImagesContext, ImagesModel, ProviderImagesOptions } from "./types.ts";
 

packages/ai/src/index.ts

@@ -1,6 +1,48 @@
-import { registerBuiltInImagesApiProviders } from "./providers/register-builtins.ts";
+export type { Static, TSchema } from "typebox";
+export { Type } from "typebox";
 
-export * from "./base.ts";
-export * from "./providers/register-builtins.ts";
-
-registerBuiltInImagesApiProviders();
+// Core only, side-effect free: no generated catalogs, no provider factories,
+// no api-registry, no OAuth implementations, no compat. Provider factories
+// live under "@earendil-works/pi-ai/providers/*", API implementations under
+// "@earendil-works/pi-ai/api/*", the old global API under
+// "@earendil-works/pi-ai/compat".
+export type { AnthropicEffort, AnthropicOptions, AnthropicThinkingDisplay } from "./api/anthropic-messages.ts";
+export type { AzureOpenAIResponsesOptions } from "./api/azure-openai-responses.ts";
+export type { BedrockOptions, BedrockThinkingDisplay } from "./api/bedrock-converse-stream.ts";
+export type { GoogleOptions } from "./api/google-generative-ai.ts";
+export type { GoogleThinkingLevel } from "./api/google-shared.ts";
+export type { GoogleVertexOptions } from "./api/google-vertex.ts";
+export * from "./api/lazy.ts";
+export type { MistralOptions } from "./api/mistral-conversations.ts";
+export type { OpenAICodexResponsesOptions, OpenAICodexWebSocketDebugStats } from "./api/openai-codex-responses.ts";
+export type { OpenAICompletionsOptions } from "./api/openai-completions.ts";
+export type { OpenAIResponsesOptions } from "./api/openai-responses.ts";
+export * from "./auth/context.ts";
+export * from "./auth/credential-store.ts";
+export * from "./auth/helpers.ts";
+export * from "./auth/types.ts";
+export * from "./images-models.ts";
+export * from "./models.ts";
+export * from "./providers/faux.ts";
+export * from "./session-resources.ts";
+export * from "./types.ts";
+export * from "./utils/diagnostics.ts";
+export * from "./utils/event-stream.ts";
+export * from "./utils/json-parse.ts";
+export type {
+	OAuthAuthInfo,
+	OAuthCredentials,
+	OAuthDeviceCodeInfo,
+	OAuthLoginCallbacks,
+	OAuthPrompt,
+	OAuthProvider,
+	OAuthProviderId,
+	OAuthProviderInfo,
+	OAuthProviderInterface,
+	OAuthSelectOption,
+	OAuthSelectPrompt,
+} from "./utils/oauth/types.ts";
+export * from "./utils/overflow.ts";
+export * from "./utils/retry.ts";
+export * from "./utils/typebox-helpers.ts";
+export * from "./utils/validation.ts";

packages/ai/src/legacy-api-aliases.ts

@@ -0,0 +1,108 @@
+import { anthropicMessagesApi } from "./api/anthropic-messages.lazy.ts";
+import type { AnthropicOptions } from "./api/anthropic-messages.ts";
+import { azureOpenAIResponsesApi } from "./api/azure-openai-responses.lazy.ts";
+import type { AzureOpenAIResponsesOptions } from "./api/azure-openai-responses.ts";
+import { googleGenerativeAIApi } from "./api/google-generative-ai.lazy.ts";
+import type { GoogleOptions } from "./api/google-generative-ai.ts";
+import { googleVertexApi } from "./api/google-vertex.lazy.ts";
+import type { GoogleVertexOptions } from "./api/google-vertex.ts";
+import { mistralConversationsApi } from "./api/mistral-conversations.lazy.ts";
+import type { MistralOptions } from "./api/mistral-conversations.ts";
+import { openAICodexResponsesApi } from "./api/openai-codex-responses.lazy.ts";
+import type { OpenAICodexResponsesOptions } from "./api/openai-codex-responses.ts";
+import { openAICompletionsApi } from "./api/openai-completions.lazy.ts";
+import type { OpenAICompletionsOptions } from "./api/openai-completions.ts";
+import { openAIResponsesApi } from "./api/openai-responses.lazy.ts";
+import type { OpenAIResponsesOptions } from "./api/openai-responses.ts";
+import type { SimpleStreamOptions, StreamFunction } from "./types.ts";
+
+const anthropicMessagesStreams = anthropicMessagesApi();
+const azureOpenAIResponsesStreams = azureOpenAIResponsesApi();
+const googleGenerativeAIStreams = googleGenerativeAIApi();
+const googleVertexStreams = googleVertexApi();
+const mistralConversationsStreams = mistralConversationsApi();
+const openAICodexResponsesStreams = openAICodexResponsesApi();
+const openAICompletionsStreams = openAICompletionsApi();
+const openAIResponsesStreams = openAIResponsesApi();
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/anthropic-messages` or `anthropicMessagesApi().stream`. */
+export const streamAnthropic = anthropicMessagesStreams.stream as StreamFunction<
+	"anthropic-messages",
+	AnthropicOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/anthropic-messages` or `anthropicMessagesApi().streamSimple`. */
+export const streamSimpleAnthropic = anthropicMessagesStreams.streamSimple as StreamFunction<
+	"anthropic-messages",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/azure-openai-responses` or `azureOpenAIResponsesApi().stream`. */
+export const streamAzureOpenAIResponses = azureOpenAIResponsesStreams.stream as StreamFunction<
+	"azure-openai-responses",
+	AzureOpenAIResponsesOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/azure-openai-responses` or `azureOpenAIResponsesApi().streamSimple`. */
+export const streamSimpleAzureOpenAIResponses = azureOpenAIResponsesStreams.streamSimple as StreamFunction<
+	"azure-openai-responses",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/google-generative-ai` or `googleGenerativeAIApi().stream`. */
+export const streamGoogle = googleGenerativeAIStreams.stream as StreamFunction<"google-generative-ai", GoogleOptions>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/google-generative-ai` or `googleGenerativeAIApi().streamSimple`. */
+export const streamSimpleGoogle = googleGenerativeAIStreams.streamSimple as StreamFunction<
+	"google-generative-ai",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/google-vertex` or `googleVertexApi().stream`. */
+export const streamGoogleVertex = googleVertexStreams.stream as StreamFunction<"google-vertex", GoogleVertexOptions>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/google-vertex` or `googleVertexApi().streamSimple`. */
+export const streamSimpleGoogleVertex = googleVertexStreams.streamSimple as StreamFunction<
+	"google-vertex",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/mistral-conversations` or `mistralConversationsApi().stream`. */
+export const streamMistral = mistralConversationsStreams.stream as StreamFunction<
+	"mistral-conversations",
+	MistralOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/mistral-conversations` or `mistralConversationsApi().streamSimple`. */
+export const streamSimpleMistral = mistralConversationsStreams.streamSimple as StreamFunction<
+	"mistral-conversations",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/openai-codex-responses` or `openAICodexResponsesApi().stream`. */
+export const streamOpenAICodexResponses = openAICodexResponsesStreams.stream as StreamFunction<
+	"openai-codex-responses",
+	OpenAICodexResponsesOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/openai-codex-responses` or `openAICodexResponsesApi().streamSimple`. */
+export const streamSimpleOpenAICodexResponses = openAICodexResponsesStreams.streamSimple as StreamFunction<
+	"openai-codex-responses",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/openai-completions` or `openAICompletionsApi().stream`. */
+export const streamOpenAICompletions = openAICompletionsStreams.stream as StreamFunction<
+	"openai-completions",
+	OpenAICompletionsOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/openai-completions` or `openAICompletionsApi().streamSimple`. */
+export const streamSimpleOpenAICompletions = openAICompletionsStreams.streamSimple as StreamFunction<
+	"openai-completions",
+	SimpleStreamOptions
+>;
+
+/** @deprecated Use `stream` from `@earendil-works/pi-ai/api/openai-responses` or `openAIResponsesApi().stream`. */
+export const streamOpenAIResponses = openAIResponsesStreams.stream as StreamFunction<
+	"openai-responses",
+	OpenAIResponsesOptions
+>;
+/** @deprecated Use `streamSimple` from `@earendil-works/pi-ai/api/openai-responses` or `openAIResponsesApi().streamSimple`. */
+export const streamSimpleOpenAIResponses = openAIResponsesStreams.streamSimple as StreamFunction<
+	"openai-responses",
+	SimpleStreamOptions
+>;

packages/ai/src/models.ts

@@ -1,39 +1,385 @@
-import { MODELS } from "./models.generated.ts";
-import type { Api, KnownProvider, Model, ModelThinkingLevel, Usage } from "./types.ts";
+import { lazyStream } from "./api/lazy.ts";
+import { defaultProviderAuthContext as defaultAuthContext } from "./auth/context.ts";
+import { InMemoryCredentialStore } from "./auth/credential-store.ts";
+import { ModelsError, resolveProviderAuth } from "./auth/resolve.ts";
+import type { AuthContext, AuthResult, CredentialStore, ProviderAuth } from "./auth/types.ts";
+import type {
+	Api,
+	ApiStreamOptions,
+	AssistantMessage,
+	AssistantMessageEventStream,
+	Context,
+	Model,
+	ModelThinkingLevel,
+	ProviderHeaders,
+	ProviderStreams,
+	SimpleStreamOptions,
+	StreamOptions,
+	Usage,
+} from "./types.ts";
 
-const modelRegistry: Map<string, Map<string, Model<Api>>> = new Map();
+export { type AuthModel, ModelsError, type ModelsErrorCode } from "./auth/resolve.ts";
 
-// Initialize registry from MODELS on module load
-for (const [provider, models] of Object.entries(MODELS)) {
-	const providerModels = new Map<string, Model<Api>>();
-	for (const [id, model] of Object.entries(models)) {
-		providerModels.set(id, model as Model<Api>);
+/**
+ * A provider is the concrete runtime unit. It owns id/name/base metadata,
+ * auth methods, model listing, and stream behavior.
+ *
+ * `TApi` lets concrete provider factories declare which APIs their models
+ * use (e.g. `openaiProvider(): Provider<"openai-responses" | "openai-completions">`),
+ * giving typed model lists to direct factory users. Inside a `Models`
+ * collection providers are held as `Provider<Api>`.
+ */
+export interface Provider<TApi extends Api = Api> {
+	readonly id: string;
+	readonly name: string;
+
+	readonly baseUrl?: string;
+	readonly headers?: ProviderHeaders;
+
+	/**
+	 * Required: at least one of `apiKey`/`oauth`. Every provider has auth
+	 * semantics — even providers with only ambient credentials (env vars, AWS
+	 * profiles, ADC files) and keyless local servers provide `apiKey` auth
+	 * whose `resolve()` reports whether the provider is configured.
+	 * `Models.getAuth()` returns undefined when the provider is unconfigured.
+	 */
+	readonly auth: ProviderAuth;
+
+	/**
+	 * Current known models, sync. Static providers return their catalog;
+	 * dynamic providers return the list as of the last `refreshModels()`
+	 * (empty before the first). Must not throw; `Models` treats a throwing
+	 * implementation as having no models.
+	 */
+	getModels(): readonly Model<TApi>[];
+
+	/**
+	 * Dynamic providers only: fetch and update the model list. Side-effect-free
+	 * discovery (no loading/downloading); provider-specific model lifecycle
+	 * belongs in app commands. Concurrent calls share one in-flight fetch.
+	 * May reject (network); on rejection the model list stays at its last-known
+	 * state and a later call retries.
+	 */
+	refreshModels?(): Promise<void>;
+
+	stream<T extends TApi>(
+		model: Model<T>,
+		context: Context,
+		options?: ApiStreamOptions<T>,
+	): AssistantMessageEventStream;
+
+	streamSimple(model: Model<TApi>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream;
+}
+
+/**
+ * Runtime collection of providers plus auth application and stream
+ * convenience. Providers own stream behavior; `Models` resolves auth and
+ * delegates each request to the provider that owns the model.
+ */
+export interface Models {
+	getProviders(): readonly Provider[];
+	getProvider(id: string): Provider | undefined;
+
+	/**
+	 * Sync read of last-known models from one provider or all providers.
+	 * Best-effort: a provider whose `getModels()` throws yields no models.
+	 */
+	getModels(provider?: string): readonly Model<Api>[];
+
+	/**
+	 * Sync runtime model lookup against last-known lists. Dynamic model lists
+	 * are typed as `Model<Api>`; narrow with the `hasApi()` type guard.
+	 */
+	getModel(provider: string, id: string): Model<Api> | undefined;
+
+	/**
+	 * Ask dynamic providers to re-fetch their model lists. With a provider id,
+	 * rejects with `ModelsError` ("model_source") on that provider's fetch
+	 * failure; without one, refreshes all providers concurrently best-effort.
+	 * Static providers (no `refreshModels`) are no-ops.
+	 */
+	refresh(provider?: string): Promise<void>;
+
+	/**
+	 * Resolve request auth for a model. Includes a source label for status UI.
+	 * Resolves `undefined` when the provider is unknown or unconfigured.
+	 * Rejects with `ModelsError`: code "oauth" when a token refresh fails (the
+	 * stored credential is preserved for retry; re-login fixes it), code "auth"
+	 * when api-key resolution or the credential store fails. Request paths
+	 * surface rejections as stream errors; status/availability UIs catch them
+	 * and render "needs re-login" instead of treating them as unconfigured.
+	 */
+	getAuth(model: Model<Api>): Promise<AuthResult | undefined>;
+
+	stream<TApi extends Api>(
+		model: Model<TApi>,
+		context: Context,
+		options?: ApiStreamOptions<TApi>,
+	): AssistantMessageEventStream;
+
+	complete<TApi extends Api>(
+		model: Model<TApi>,
+		context: Context,
+		options?: ApiStreamOptions<TApi>,
+	): Promise<AssistantMessage>;
+
+	streamSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream;
+	completeSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): Promise<AssistantMessage>;
+}
+
+export interface MutableModels extends Models {
+	/** Upsert/replace by provider.id. Provider ids are unique. */
+	setProvider(provider: Provider): void;
+	deleteProvider(id: string): void;
+	clearProviders(): void;
+}
+
+export interface CreateModelsOptions {
+	credentials?: CredentialStore;
+	authContext?: AuthContext;
+}
+
+class ModelsImpl implements MutableModels {
+	private providers = new Map<string, Provider>();
+	private credentials: CredentialStore;
+	private authContext: AuthContext;
+
+	constructor(options?: CreateModelsOptions) {
+		this.credentials = options?.credentials ?? new InMemoryCredentialStore();
+		this.authContext = options?.authContext ?? defaultAuthContext();
+	}
+
+	setProvider(provider: Provider): void {
+		this.providers.set(provider.id, provider);
+	}
+
+	deleteProvider(id: string): void {
+		this.providers.delete(id);
+	}
+
+	clearProviders(): void {
+		this.providers.clear();
+	}
+
+	getProviders(): readonly Provider[] {
+		return Array.from(this.providers.values());
+	}
+
+	getProvider(id: string): Provider | undefined {
+		return this.providers.get(id);
+	}
+
+	getModels(provider?: string): readonly Model<Api>[] {
+		if (provider !== undefined) {
+			const entry = this.providers.get(provider);
+			if (!entry) return [];
+			try {
+				return entry.getModels();
+			} catch {
+				return [];
+			}
+		}
+
+		const models: Model<Api>[] = [];
+		for (const entry of this.providers.values()) {
+			try {
+				models.push(...entry.getModels());
+			} catch {
+				// Best-effort: ill-behaved providers yield no models.
+			}
+		}
+		return models;
+	}
+
+	getModel(provider: string, id: string): Model<Api> | undefined {
+		return this.getModels(provider).find((model) => model.id === id);
+	}
+
+	async refresh(provider?: string): Promise<void> {
+		if (provider !== undefined) {
+			const entry = this.providers.get(provider);
+			if (!entry?.refreshModels) return;
+			try {
+				await entry.refreshModels();
+			} catch (error) {
+				if (error instanceof ModelsError) throw error;
+				throw new ModelsError("model_source", `Model refresh failed for ${provider}`, { cause: error });
+			}
+			return;
+		}
+
+		// Cannot reject: the async mapper turns even sync throws from ill-behaved
+		// providers into rejections, and allSettled captures all of them.
+		await Promise.allSettled(Array.from(this.providers.values(), async (entry) => entry.refreshModels?.()));
+	}
+
+	async getAuth(model: Model<Api>): Promise<AuthResult | undefined> {
+		const provider = this.providers.get(model.provider);
+		if (!provider) return undefined;
+		return resolveProviderAuth(provider, model, this.credentials, this.authContext);
+	}
+
+	private requireProvider(model: Model<Api>): Provider {
+		const provider = this.providers.get(model.provider);
+		if (!provider) {
+			throw new ModelsError("provider", `Unknown provider: ${model.provider}`);
+		}
+		return provider;
+	}
+
+	private async applyAuth<TOptions extends StreamOptions>(
+		model: Model<Api>,
+		options: TOptions | undefined,
+	): Promise<{ requestModel: Model<Api>; requestOptions: TOptions | undefined }> {
+		const resolution = await resolveProviderAuth(
+			this.requireProvider(model),
+			model,
+			this.credentials,
+			this.authContext,
+			{
+				apiKey: options?.apiKey,
+				env: options?.env,
+			},
+		);
+		const auth = resolution?.auth;
+		if (!auth) return { requestModel: model, requestOptions: options };
+
+		const requestModel = auth.baseUrl ? { ...model, baseUrl: auth.baseUrl } : model;
+
+		// Explicit request options win per-field; headers/env merge per key.
+		const apiKey = options?.apiKey ?? auth.apiKey;
+		const headers = auth.headers || options?.headers ? { ...auth.headers, ...options?.headers } : undefined;
+		const env = resolution.env || options?.env ? { ...(resolution.env ?? {}), ...(options?.env ?? {}) } : undefined;
+		const requestOptions = { ...options, apiKey, headers, env } as TOptions;
+
+		return { requestModel, requestOptions };
+	}
+
+	stream<TApi extends Api>(
+		model: Model<TApi>,
+		context: Context,
+		options?: ApiStreamOptions<TApi>,
+	): AssistantMessageEventStream {
+		return lazyStream(model, async () => {
+			const provider = this.requireProvider(model);
+			const { requestModel, requestOptions } = await this.applyAuth(model, options as StreamOptions | undefined);
+			return provider.stream(requestModel as Model<TApi>, context, requestOptions as ApiStreamOptions<TApi>);
+		});
+	}
+
+	async complete<TApi extends Api>(
+		model: Model<TApi>,
+		context: Context,
+		options?: ApiStreamOptions<TApi>,
+	): Promise<AssistantMessage> {
+		return this.stream(model, context, options).result();
+	}
+
+	streamSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): AssistantMessageEventStream {
+		return lazyStream(model, async () => {
+			const provider = this.requireProvider(model);
+			const { requestModel, requestOptions } = await this.applyAuth(model, options);
+			return provider.streamSimple(requestModel, context, requestOptions);
+		});
+	}
+
+	async completeSimple(model: Model<Api>, context: Context, options?: SimpleStreamOptions): Promise<AssistantMessage> {
+		return this.streamSimple(model, context, options).result();
 	}
-	modelRegistry.set(provider, providerModels);
 }
 
-type ModelApi<
-	TProvider extends KnownProvider,
-	TModelId extends keyof (typeof MODELS)[TProvider],
-> = (typeof MODELS)[TProvider][TModelId] extends { api: infer TApi } ? (TApi extends Api ? TApi : never) : never;
-
-export function getModel<TProvider extends KnownProvider, TModelId extends keyof (typeof MODELS)[TProvider]>(
-	provider: TProvider,
-	modelId: TModelId,
-): Model<ModelApi<TProvider, TModelId>> {
-	const providerModels = modelRegistry.get(provider);
-	return providerModels?.get(modelId as string) as Model<ModelApi<TProvider, TModelId>>;
+export function createModels(options?: CreateModelsOptions): MutableModels {
+	return new ModelsImpl(options);
 }
 
-export function getProviders(): KnownProvider[] {
-	return Array.from(modelRegistry.keys()) as KnownProvider[];
+export interface CreateProviderOptions<TApi extends Api = Api> {
+	id: string;
+	/** Display name. Default: `id`. */
+	name?: string;
+	baseUrl?: string;
+	headers?: ProviderHeaders;
+	/** Required — every provider has auth semantics, even ambient/keyless ones. */
+	auth: ProviderAuth;
+	/** Initial model list (empty for purely dynamic providers). */
+	models: readonly Model<TApi>[];
+	/**
+	 * Dynamic providers: fetch the current list. Stored on success; concurrent
+	 * calls share one in-flight fetch. May reject: the stored list then stays
+	 * at its last-known state, the rejection propagates to the caller of
+	 * `refreshModels()` (wrapped as ModelsError "model_source" by
+	 * `Models.refresh(provider)`), and a later call retries.
+	 */
+	refreshModels?: () => Promise<readonly Model<TApi>[]>;
+	/** Single implementation, or map keyed by `model.api` for mixed-API providers. */
+	api: ProviderStreams | Partial<Record<TApi, ProviderStreams>>;
 }
 
-export function getModels<TProvider extends KnownProvider>(
-	provider: TProvider,
-): Model<ModelApi<TProvider, keyof (typeof MODELS)[TProvider]>>[] {
-	const models = modelRegistry.get(provider);
-	return models ? (Array.from(models.values()) as Model<ModelApi<TProvider, keyof (typeof MODELS)[TProvider]>>[]) : [];
+/**
+ * Builds a provider from parts. Built-in provider factories and models.json
+ * custom providers both go through this. A single `api` streams all models;
+ * an `api` map dispatches on `model.api`, and a model whose api has no entry
+ * produces a stream error.
+ */
+export function createProvider<TApi extends Api = Api>(input: CreateProviderOptions<TApi>): Provider<TApi> {
+	let models = input.models;
+	let inflightRefresh: Promise<void> | undefined;
+	const refreshModels = input.refreshModels;
+	const single =
+		typeof (input.api as ProviderStreams).stream === "function" ? (input.api as ProviderStreams) : undefined;
+	const byApi = single ? undefined : (input.api as Partial<Record<string, ProviderStreams>>);
+
+	const apiFor = (model: Model<Api>): ProviderStreams | undefined => single ?? byApi?.[model.api];
+
+	const dispatch = (
+		model: Model<Api>,
+		run: (streams: ProviderStreams) => AssistantMessageEventStream,
+	): AssistantMessageEventStream => {
+		const streams = apiFor(model);
+		if (!streams) {
+			return lazyStream(model, async () => {
+				throw new ModelsError("stream", `Provider ${input.id} has no API implementation for "${model.api}"`);
+			});
+		}
+		return run(streams);
+	};
+
+	return {
+		id: input.id,
+		name: input.name ?? input.id,
+		baseUrl: input.baseUrl,
+		headers: input.headers,
+		auth: input.auth,
+		getModels: () => models,
+		refreshModels: refreshModels
+			? () => {
+					inflightRefresh ??= (async () => {
+						try {
+							models = await refreshModels();
+						} finally {
+							inflightRefresh = undefined;
+						}
+					})();
+					return inflightRefresh;
+				}
+			: undefined,
+		stream: (model, context, options) => dispatch(model, (streams) => streams.stream(model, context, options)),
+		streamSimple: (model, context, options) =>
+			dispatch(model, (streams) => streams.streamSimple(model, context, options)),
+	};
+}
+
+/**
+ * Runtime-checked narrowing for dynamically looked-up models:
+ *
+ * ```ts
+ * const model = models.getModel("anthropic", "claude-opus-4-7");
+ * if (model && hasApi(model, "anthropic-messages")) {
+ *   // model: Model<"anthropic-messages">, stream options fully typed
+ * }
+ * ```
+ */
+export function hasApi<TApi extends Api>(model: Model<Api>, api: TApi): model is Model<TApi> {
+	return model.api === api;
 }
 
 export function calculateCost<TApi extends Api>(model: Model<TApi>, usage: Usage): Usage["cost"] {

packages/ai/src/providers/all.ts

@@ -0,0 +1,131 @@
+import { createImagesModels, type ImagesProvider, type MutableImagesModels } from "../images-models.ts";
+import { MODELS } from "../models.generated.ts";
+import { type CreateModelsOptions, createModels, type MutableModels, type Provider } from "../models.ts";
+import type { Api, KnownProvider, Model } from "../types.ts";
+import { amazonBedrockProvider } from "./amazon-bedrock.ts";
+import { antLingProvider } from "./ant-ling.ts";
+import { anthropicProvider } from "./anthropic.ts";
+import { azureOpenAIResponsesProvider } from "./azure-openai-responses.ts";
+import { cerebrasProvider } from "./cerebras.ts";
+import { cloudflareAIGatewayProvider } from "./cloudflare-ai-gateway.ts";
+import { cloudflareWorkersAIProvider } from "./cloudflare-workers-ai.ts";
+import { deepseekProvider } from "./deepseek.ts";
+import { fireworksProvider } from "./fireworks.ts";
+import { githubCopilotProvider } from "./github-copilot.ts";
+import { googleProvider } from "./google.ts";
+import { googleVertexProvider } from "./google-vertex.ts";
+import { groqProvider } from "./groq.ts";
+import { huggingfaceProvider } from "./huggingface.ts";
+import { kimiCodingProvider } from "./kimi-coding.ts";
+import { minimaxProvider } from "./minimax.ts";
+import { minimaxCnProvider } from "./minimax-cn.ts";
+import { mistralProvider } from "./mistral.ts";
+import { moonshotaiProvider } from "./moonshotai.ts";
+import { moonshotaiCnProvider } from "./moonshotai-cn.ts";
+import { nvidiaProvider } from "./nvidia.ts";
+import { openaiProvider } from "./openai.ts";
+import { openaiCodexProvider } from "./openai-codex.ts";
+import { opencodeProvider } from "./opencode.ts";
+import { opencodeGoProvider } from "./opencode-go.ts";
+import { openrouterProvider } from "./openrouter.ts";
+import { openrouterImagesProvider } from "./openrouter-images.ts";
+import { togetherProvider } from "./together.ts";
+import { vercelAIGatewayProvider } from "./vercel-ai-gateway.ts";
+import { xaiProvider } from "./xai.ts";
+import { xiaomiProvider } from "./xiaomi.ts";
+import { xiaomiTokenPlanAmsProvider } from "./xiaomi-token-plan-ams.ts";
+import { xiaomiTokenPlanCnProvider } from "./xiaomi-token-plan-cn.ts";
+import { xiaomiTokenPlanSgpProvider } from "./xiaomi-token-plan-sgp.ts";
+import { zaiProvider } from "./zai.ts";
+import { zaiCodingCnProvider } from "./zai-coding-cn.ts";
+
+type BuiltinModelApi<
+	TProvider extends KnownProvider,
+	TModelId extends keyof (typeof MODELS)[TProvider],
+> = (typeof MODELS)[TProvider][TModelId] extends { api: infer TApi } ? (TApi extends Api ? TApi : never) : never;
+
+/** Typed read of the generated built-in catalog. */
+export function getBuiltinModel<TProvider extends KnownProvider, TModelId extends keyof (typeof MODELS)[TProvider]>(
+	provider: TProvider,
+	modelId: TModelId,
+): Model<BuiltinModelApi<TProvider, TModelId>> {
+	const models = MODELS[provider] as Record<string, Model<Api>> | undefined;
+	return models?.[modelId as string] as Model<BuiltinModelApi<TProvider, TModelId>>;
+}
+
+export function getBuiltinProviders(): KnownProvider[] {
+	return Object.keys(MODELS) as KnownProvider[];
+}
+
+export function getBuiltinModels<TProvider extends KnownProvider>(
+	provider: TProvider,
+): Model<BuiltinModelApi<TProvider, keyof (typeof MODELS)[TProvider]>>[] {
+	const models = MODELS[provider] as Record<string, Model<Api>> | undefined;
+	return models
+		? (Object.values(models) as Model<BuiltinModelApi<TProvider, keyof (typeof MODELS)[TProvider]>>[])
+		: [];
+}
+
+/** All built-in providers, freshly constructed. */
+export function builtinProviders(): Provider[] {
+	return [
+		amazonBedrockProvider(),
+		antLingProvider(),
+		anthropicProvider(),
+		azureOpenAIResponsesProvider(),
+		cerebrasProvider(),
+		cloudflareAIGatewayProvider(),
+		cloudflareWorkersAIProvider(),
+		deepseekProvider(),
+		fireworksProvider(),
+		githubCopilotProvider(),
+		googleProvider(),
+		googleVertexProvider(),
+		groqProvider(),
+		huggingfaceProvider(),
+		kimiCodingProvider(),
+		minimaxProvider(),
+		minimaxCnProvider(),
+		mistralProvider(),
+		moonshotaiProvider(),
+		moonshotaiCnProvider(),
+		nvidiaProvider(),
+		openaiProvider(),
+		openaiCodexProvider(),
+		opencodeProvider(),
+		opencodeGoProvider(),
+		openrouterProvider(),
+		togetherProvider(),
+		vercelAIGatewayProvider(),
+		xaiProvider(),
+		xiaomiProvider(),
+		xiaomiTokenPlanAmsProvider(),
+		xiaomiTokenPlanCnProvider(),
+		xiaomiTokenPlanSgpProvider(),
+		zaiProvider(),
+		zaiCodingCnProvider(),
+	];
+}
+
+/** A `Models` collection with every built-in provider registered. */
+export function builtinModels(options?: CreateModelsOptions): MutableModels {
+	const models = createModels(options);
+	for (const provider of builtinProviders()) {
+		models.setProvider(provider);
+	}
+	return models;
+}
+
+/** All built-in image-generation providers, freshly constructed. */
+export function builtinImagesProviders(): ImagesProvider[] {
+	return [openrouterImagesProvider()];
+}
+
+/** An `ImagesModels` collection with every built-in image-generation provider registered. */
+export function builtinImagesModels(options?: CreateModelsOptions): MutableImagesModels {
+	const models = createImagesModels(options);
+	for (const provider of builtinImagesProviders()) {
+		models.setProvider(provider);
+	}
+	return models;
+}

packages/ai/src/providers/ant-ling.models.ts

@@ -0,0 +1,62 @@
+// This file is auto-generated by scripts/generate-models.ts
+// Do not edit manually - run 'npm run generate-models' to update
+
+import type { Model } from "../types.ts";
+
+export const ANT_LING_MODELS = {
+	"Ling-2.6-1T": {
+		id: "Ling-2.6-1T",
+		name: "Ling 2.6 1T",
+		api: "openai-completions",
+		provider: "ant-ling",
+		baseUrl: "https://api.ant-ling.com/v1",
+		compat: {"supportsStore":false,"supportsDeveloperRole":false,"supportsReasoningEffort":false,"maxTokensField":"max_tokens","thinkingFormat":"ant-ling","supportsLongCacheRetention":false},
+		reasoning: false,
+		input: ["text"],
+		cost: {
+			input: 0.06,
+			output: 0.25,
+			cacheRead: 0,
+			cacheWrite: 0,
+		},
+		contextWindow: 262144,
+		maxTokens: 65536,
+	} satisfies Model<"openai-completions">,
+	"Ling-2.6-flash": {
+		id: "Ling-2.6-flash",
+		name: "Ling 2.6 Flash",
+		api: "openai-completions",
+		provider: "ant-ling",
+		baseUrl: "https://api.ant-ling.com/v1",
+		compat: {"supportsStore":false,"supportsDeveloperRole":false,"supportsReasoningEffort":false,"maxTokensField":"max_tokens","thinkingFormat":"ant-ling","supportsLongCacheRetention":false},
+		reasoning: false,
+		input: ["text"],
+		cost: {
+			input: 0.01,
+			output: 0.02,
+			cacheRead: 0,
+			cacheWrite: 0,
+		},
+		contextWindow: 262144,
+		maxTokens: 65536,
+	} satisfies Model<"openai-completions">,
+	"Ring-2.6-1T": {
+		id: "Ring-2.6-1T",
+		name: "Ring 2.6 1T",
+		api: "openai-completions",
+		provider: "ant-ling",
+		baseUrl: "https://api.ant-ling.com/v1",
+		compat: {"supportsStore":false,"supportsDeveloperRole":false,"supportsReasoningEffort":false,"maxTokensField":"max_tokens","thinkingFormat":"ant-ling","supportsLongCacheRetention":false},
+		reasoning: true,
+		thinkingLevelMap: {"off":null,"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"xhigh"},
+		input: ["text"],
+		cost: {
+			input: 0.06,
+			output: 0.25,
+			cacheRead: 0,
+			cacheWrite: 0,
+		},
+		contextWindow: 262144,
+		maxTokens: 65536,
+	} satisfies Model<"openai-completions">,
+} as const;