diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index 5acf40dfe..83b6fbc67 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -4,7 +4,7 @@
 
 ### Added
 
-- Added a `project_trust` extension event so global and CLI extensions can decide project trust during startup and runtime cwd switches.
+- Added a `project_trust` extension event so global and CLI extensions can decide or defer project trust during startup and runtime cwd switches.
 - Added project trust gating for project-local settings, resources, instructions, and packages ([#5332](https://github.com/earendil-works/pi/pull/5332)).
 - Added the latest prompt cache hit rate to the interactive footer.
 - Exported RPC extension UI request and response types from the public API ([#5455](https://github.com/earendil-works/pi/issues/5455)).
diff --git a/packages/coding-agent/docs/extensions.md b/packages/coding-agent/docs/extensions.md
index 53152ca09..601d378ec 100644
--- a/packages/coding-agent/docs/extensions.md
+++ b/packages/coding-agent/docs/extensions.md
@@ -346,12 +346,13 @@ pi.on("project_trust", async (event, ctx) => {
   // event.cwd - current working directory
   // ctx has a limited trust context: cwd, mode, hasUI, and select/confirm/input/notify UI helpers
   if (await ctx.ui.confirm("Trust project?", event.cwd)) {
-    return { trusted: true, remember: true };
+    return { trusted: "yes", remember: true };
   }
+  return { trusted: "undecided" };
 });
 ```
 
-A `project_trust` handler must return `{ trusted }`; if a user/global or CLI extension registers this handler, it owns the decision. The first returned decision wins and suppresses the built-in trust prompt. Use `remember: true` to persist the decision; otherwise it applies only to the current process. Check `ctx.hasUI` before prompting. If no extension handles `project_trust`, normal trust resolution continues, including the built-in trust prompt when UI is available.
+A `project_trust` handler must return `{ trusted: "yes" | "no" | "undecided" }`. A user/global or CLI extension that returns `"yes"` or `"no"` owns the decision; the first yes/no decision wins and suppresses the built-in trust prompt. Use `remember: true` to persist a yes/no decision; otherwise it applies only to the current process. Return `"undecided"` to let later handlers or the built-in trust flow decide. Check `ctx.hasUI` before prompting. If no handler returns yes/no, normal trust resolution continues, including the built-in trust prompt when UI is available.
 
 ### Resource Events
 
@@ -2586,7 +2587,7 @@ All examples in [examples/extensions/](../examples/extensions/).
 | `shutdown-command.ts` | Graceful shutdown command | `registerCommand`, `shutdown()` |
 | **Events & Gates** |||
 | `permission-gate.ts` | Block dangerous commands | `on("tool_call")`, `ui.confirm` |
-| `project-trust.ts` | Decide project trust from a user/global or CLI extension | `on("project_trust")`, trust UI, required trust result |
+| `project-trust.ts` | Decide or defer project trust from a user/global or CLI extension | `on("project_trust")`, trust UI, required trust result |
 | `protected-paths.ts` | Block writes to specific paths | `on("tool_call")` |
 | `confirm-destructive.ts` | Confirm session changes | `on("session_before_switch")`, `on("session_before_fork")` |
 | `dirty-repo-guard.ts` | Warn on dirty git repo | `on("session_before_*")`, `exec` |
diff --git a/packages/coding-agent/examples/extensions/project-trust.ts b/packages/coding-agent/examples/extensions/project-trust.ts
index 66020a548..6234bc249 100644
--- a/packages/coding-agent/examples/extensions/project-trust.ts
+++ b/packages/coding-agent/examples/extensions/project-trust.ts
@@ -20,13 +20,14 @@ export default function (pi: ExtensionAPI) {
 	loadCount++;
 
 	// Multiple handlers in one extension are allowed. The first handler that returns
-	// { trusted } wins and suppresses the built-in trust prompt. A project_trust
-	// handler must return a decision.
+	// { trusted: "yes" } or { trusted: "no" } wins and suppresses the built-in
+	// trust prompt. Return { trusted: "undecided" } to let another handler or the
+	// built-in flow decide.
 	pi.on("project_trust", async (event, ctx): Promise<ProjectTrustEventResult> => {
 		ctx.ui.notify(`project_trust fired for ${event.cwd} (mode: ${ctx.mode}, load: ${loadCount})`, "info");
 
 		if (!ctx.hasUI) {
-			return { trusted: false };
+			return { trusted: "undecided" };
 		}
 
 		const choice = await ctx.ui.select(`Project trust for:\n${event.cwd}`, [
@@ -34,23 +35,27 @@ export default function (pi: ExtensionAPI) {
 			"Trust with note and remember",
 			"Trust this session",
 			"Do not trust this session",
+			"Let built-in prompt decide",
 		]);
 
 		if (choice === "Trust with note and remember") {
 			const note = await ctx.ui.input("Project trust note", "Optional note for this demo");
 			ctx.ui.notify(note ? `Recorded demo note: ${note}` : "No demo note entered", "info");
-			return { trusted: true, remember: true };
+			return { trusted: "yes", remember: true };
 		}
 		if (choice === "Trust and remember") {
-			return { trusted: true, remember: true };
+			return { trusted: "yes", remember: true };
 		}
 		if (choice === "Trust this session") {
-			return { trusted: true };
+			return { trusted: "yes" };
 		}
 		if (choice === "Do not trust this session") {
-			return { trusted: false };
+			return { trusted: "no" };
 		}
-		return { trusted: false };
+		if (choice === "Let built-in prompt decide") {
+			return { trusted: "undecided" };
+		}
+		return { trusted: "undecided" };
 	});
 
 	pi.on("session_start", (_event, ctx) => {
diff --git a/packages/coding-agent/src/core/extensions/index.ts b/packages/coding-agent/src/core/extensions/index.ts
index a20887ed8..3ed7a6625 100644
--- a/packages/coding-agent/src/core/extensions/index.ts
+++ b/packages/coding-agent/src/core/extensions/index.ts
@@ -100,6 +100,7 @@ export type {
 	ModelSelectSource,
 	ProjectTrustContext,
 	ProjectTrustEvent,
+	ProjectTrustEventDecision,
 	ProjectTrustEventResult,
 	ProjectTrustHandler,
 	// Provider Registration
diff --git a/packages/coding-agent/src/core/extensions/runner.ts b/packages/coding-agent/src/core/extensions/runner.ts
index db4ba0be3..3030b65d1 100644
--- a/packages/coding-agent/src/core/extensions/runner.ts
+++ b/packages/coding-agent/src/core/extensions/runner.ts
@@ -202,13 +202,16 @@ export async function emitProjectTrustEvent(
 	const errors: ExtensionError[] = [];
 	for (const ext of extensionsResult.extensions) {
 		// A single extension may register multiple handlers for the same event.
-		// The first project_trust handler that returns a decision wins.
+		// The first project_trust handler that returns yes/no wins; undecided falls through.
 		const handlers = ext.handlers.get("project_trust");
 		if (!handlers || handlers.length === 0) continue;
 
 		for (const handler of handlers) {
 			try {
 				const handlerResult = (await handler(event, ctx)) as ProjectTrustEventResult;
+				if (handlerResult.trusted === "undecided") {
+					continue;
+				}
 				return { result: handlerResult, errors };
 			} catch (error) {
 				errors.push({
diff --git a/packages/coding-agent/src/core/extensions/types.ts b/packages/coding-agent/src/core/extensions/types.ts
index 9fd3ffdfd..7575d8af3 100644
--- a/packages/coding-agent/src/core/extensions/types.ts
+++ b/packages/coding-agent/src/core/extensions/types.ts
@@ -503,8 +503,10 @@ export interface ProjectTrustEvent {
 	cwd: string;
 }
 
+export type ProjectTrustEventDecision = "yes" | "no" | "undecided";
+
 export interface ProjectTrustEventResult {
-	trusted: boolean;
+	trusted: ProjectTrustEventDecision;
 	remember?: boolean;
 }
 
diff --git a/packages/coding-agent/src/index.ts b/packages/coding-agent/src/index.ts
index 677c030b2..398f5430d 100644
--- a/packages/coding-agent/src/index.ts
+++ b/packages/coding-agent/src/index.ts
@@ -100,6 +100,7 @@ export type {
 	MessageRenderOptions,
 	ProjectTrustContext,
 	ProjectTrustEvent,
+	ProjectTrustEventDecision,
 	ProjectTrustEventResult,
 	ProjectTrustHandler,
 	ProviderConfig,
diff --git a/packages/coding-agent/src/main.ts b/packages/coding-agent/src/main.ts
index 4387af6d4..335d814aa 100644
--- a/packages/coding-agent/src/main.ts
+++ b/packages/coding-agent/src/main.ts
@@ -648,10 +648,11 @@ async function resolveProjectTrusted(options: {
 			options.onExtensionError?.(`Extension "${error.extensionPath}" project_trust error: ${error.error}`);
 		}
 		if (result) {
+			const trusted = result.trusted === "yes";
 			if (result.remember === true) {
-				options.trustStore.set(options.cwd, result.trusted);
+				options.trustStore.set(options.cwd, trusted);
 			}
-			return result.trusted;
+			return trusted;
 		}
 	}
 
diff --git a/packages/coding-agent/test/extensions-runner.test.ts b/packages/coding-agent/test/extensions-runner.test.ts
index 0432ec39e..f49393672 100644
--- a/packages/coding-agent/test/extensions-runner.test.ts
+++ b/packages/coding-agent/test/extensions-runner.test.ts
@@ -7,8 +7,8 @@ import * as os from "node:os";
 import * as path from "node:path";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { AuthStorage } from "../src/core/auth-storage.ts";
-import { createExtensionRuntime, discoverAndLoadExtensions } from "../src/core/extensions/loader.ts";
-import { ExtensionRunner } from "../src/core/extensions/runner.ts";
+import { createExtensionRuntime, discoverAndLoadExtensions, loadExtensions } from "../src/core/extensions/loader.ts";
+import { ExtensionRunner, emitProjectTrustEvent } from "../src/core/extensions/runner.ts";
 import type {
 	ExtensionActions,
 	ExtensionContextActions,
@@ -85,6 +85,45 @@ describe("ExtensionRunner", () => {
 		getSystemPrompt: () => "",
 	};
 
+	describe("project_trust", () => {
+		it("continues past undecided handlers and returns the first yes/no decision", async () => {
+			const undecidedPath = path.join(extensionsDir, "undecided.ts");
+			const decidedPath = path.join(extensionsDir, "decided.ts");
+			fs.writeFileSync(
+				undecidedPath,
+				`export default function(pi) {
+	pi.on("project_trust", () => ({ trusted: "undecided", remember: true }));
+}`,
+			);
+			fs.writeFileSync(
+				decidedPath,
+				`export default function(pi) {
+	pi.on("project_trust", () => ({ trusted: "no", remember: true }));
+}`,
+			);
+
+			const extensionsResult = await loadExtensions([undecidedPath, decidedPath], tempDir);
+			const result = await emitProjectTrustEvent(
+				extensionsResult,
+				{ type: "project_trust", cwd: tempDir },
+				{
+					cwd: tempDir,
+					mode: "tui",
+					hasUI: false,
+					ui: {
+						select: async () => undefined,
+						confirm: async () => false,
+						input: async () => undefined,
+						notify: () => {},
+					},
+				},
+			);
+
+			expect(result.result).toEqual({ trusted: "no", remember: true });
+			expect(result.errors).toEqual([]);
+		});
+	});
+
 	describe("shortcut conflicts", () => {
 		it("warns when extension shortcut conflicts with built-in", async () => {
 			const extCode = `
diff --git a/packages/coding-agent/test/resource-loader.test.ts b/packages/coding-agent/test/resource-loader.test.ts
index 779f60640..abbe89755 100644
--- a/packages/coding-agent/test/resource-loader.test.ts
+++ b/packages/coding-agent/test/resource-loader.test.ts
@@ -199,7 +199,7 @@ Project skill`,
 				join(userExtDir, "user.ts"),
 				`globalThis[${JSON.stringify(loadCountKey)}] = (globalThis[${JSON.stringify(loadCountKey)}] ?? 0) + 1;
 export default function(pi) {
-	pi.on("project_trust", () => ({ trusted: true }));
+	pi.on("project_trust", () => ({ trusted: "yes" }));
 	pi.registerCommand("user-trust", {
 		description: "user trust",
 		handler: async () => {},