1 commit

Author	SHA1	Message	Date
Shaojin Wen	d36f12c4c4	feat(session): auto-title sessions via fast model, add /rename --auto (#3540) ... * feat(session): auto-title sessions via fast model, add /rename --auto The /rename work in #3093 generates kebab-case titles only when the user explicitly runs `/rename` with no args; until they do, the session picker shows the first user prompt (often truncated or misleading). This change adds a sentence-case auto-title that fires once per session after the first assistant turn, using the configured fast model. New service: `packages/core/src/services/sessionTitle.ts` — `tryGenerateSessionTitle(config, signal)` returns a discriminated outcome (`{ok: true, title, modelUsed}` | `{ok: false, reason}`) so callers can either handle failures generically or map reasons to actionable messages. Prompt shape: 3-7 words, sentence case, good/bad examples including a CJK row, JSON schema enforced via `baseLlmClient.generateJson`. `maxAttempts: 1` — titles are cosmetic metadata and shouldn't fight rate limits. Trigger point: `ChatRecordingService.maybeTriggerAutoTitle` runs after `recordAssistantTurn`. Fire-and-forget promise, guarded by: - `currentCustomTitle` — don't overwrite any existing title. - `autoTitleController` doubles as in-flight flag; a second turn while the first is still pending is a no-op. - `autoTitleAttempts` cap of 3 — the first assistant turn may be a pure tool-call with no user-visible text; retry for a handful of turns until a title lands. Cap bounds total waste. - `!config.isInteractive()` — headless CLI (`qwen -p`, CI) never auto- titles; spending fast-model tokens on a one-shot session is waste. - `autoTitleDisabledByEnv()` — `QWEN_DISABLE_AUTO_TITLE=1` opt-out. - `config.getFastModel()` falsy — skip entirely rather than falling back to the main model; auto-titling on main-model tokens is too expensive to be silent. Persistence: `CustomTitleRecordPayload` grows a `titleSource: 'auto' | 'manual'` field. Absent on pre-change records (treated as `undefined` → manual, safe default so a user's pre-upgrade `/rename` is never silently reclassified). `SessionPicker` renders `titleSource === 'auto'` titles in dim (secondary) color; manual stays full contrast. On resume, the persisted source is rehydrated into `currentTitleSource` — without this, finalize's re-append would rewrite an auto title as manual on every resume cycle. Cross-process manual-rename guard: when two CLI tabs target the same JSONL, in-memory state can diverge. Before writing an auto record, the IIFE re-reads the file via `sessionService.getSessionTitleInfo`. If a `/rename` from another process landed as manual, bail and sync local state — never clobber a deliberately-chosen manual title with a model guess. Cost is one 64KB tail read per successful generation. `finalize()` aborts the in-flight controller before re-appending the title record. Session switch / shutdown doesn't have to wait on a slow fast-model call. New user-facing command: `/rename --auto` regenerates via the same generator — explicit user trigger, overwrites whatever's there (manual or auto) because the user asked. Errors route through `autoFailureMessage(reason)` so `empty_history`, `model_error`, `aborted`, etc. each get actionable guidance rather than a generic "could not generate". `/rename -- --literal-name` is the sentinel for titles that start with `--`; unknown `--flag` tokens error with a hint pointing at the sentinel. Existing `/rename <name>` and bare `/rename` (kebab-case via existing path) are unchanged, except the kebab path now prefers fast model when available and runs its output through `stripTerminalControlSequences` (same ANSI/OSC-8 hardening as the sentence-case path). New shared util: `packages/core/src/utils/terminalSafe.ts` — `stripTerminalControlSequences(s)` strips OSC (\x1b]...\x07|\x1b\\), CSI (\x1b[...[a-zA-Z]), SS2/SS3 leaders, and C0/C1/DEL as a backstop. A model-returned `\x1b[2J` or OSC-8 hyperlink escape would otherwise execute on every SessionPicker render; both sentence-case and kebab paths now route titles through the helper before they reach the JSONL or the UI. Tail-read extractor: `extractLastJsonStringFields(text, primaryKey, otherKeys, lineContains)` reads multiple fields from the same matching line in a single pass. Two separate tail scans could return a mismatched pair (primary from a newer record, secondary from an older one with only the primary set); the new helper guarantees the pair is atomic. Validates a proper closing quote on the primary value so a crash-truncated trailing record can't win the latest-match race. `readLastJsonStringFieldsSync` is its file-reading wrapper — same tail-window fast path and full-file fallback as the single-field version, plus a `MAX_FULL_SCAN_BYTES = 64MB` cap so a corrupt multi-GB session file can't freeze the picker. Session reads now open with `O_NOFOLLOW` (falls back to plain RDONLY on Windows where the constant isn't exposed) — defense in depth against a symlink planted in `~/.qwen/projects/<proj>/chats/`. Character handling: `flattenToTail` on the LLM prompt drops a dangling low surrogate after `slice(-1000)` — otherwise a CJK supplementary char or emoji cut mid-pair produces invalid UTF-16 that some providers 400. `sanitizeTitle` applies the same surrogate scrub after max-length trim, and strips paired CJK brackets (`「」 『』 【】 〈〉 《》`) as whole units so a `【Draft】 Fix login` doesn't leave a dangling `】` after leading-char strip. `lineContains` in the title reader is tightened from the loose substring `'custom_title'` to `'"subtype":"custom_title"'` so user text containing the literal `custom_title` can't shadow a real record. Tests: 46 new unit tests across - `sessionTitle.test.ts` (22): success/all-failure-reasons, tool-call filter, tail-slice, surrogate scrub, ANSI/OSC-8 strip, CJK brackets. - `chatRecordingService.autoTitle.test.ts` (15): trigger/skip matrix, in-flight guard, abort propagation on finalize, manual/auto/legacy resume symmetry, cross-process race, env opt-out, retry-after- transient. - `sessionStorageUtils.test.ts` (13): single-pass extractor, straddle boundary, truncated trailing record, lineContains, multi-field atom. - `renameCommand.test.ts` (8): `--auto` success, all reasons, sentinel, unknown-flag hint, positional rejection, manual/SessionService fallbacks. * docs(session): design doc for auto session titles Matches the session-recap design doc shape (Overview / Triggers / Architecture / Prompt Design / History Filtering / Persistence / Concurrency / Configuration / Observability / Out of Scope) and adds a Security Hardening section unique to the title path — titles render directly in the picker and persist in user-readable JSONL, so LLM-returned control sequences are an attack surface the recap path doesn't have. Captures decisions a code-only reader has to reverse-engineer: - Why `maxAttempts: 1` (best-effort cosmetic metadata; no retry loop). - Why `autoTitleAttempts` cap is 3 (first turn can be pure tool-call). - Why the auto trigger does NOT fall back to the main model but session-recap does (auto-title fires on every turn; silently charging main-model tokens is a bill surprise). - Why `titleSource: undefined` stays unwritten on legacy records (no rewrite risks silently reclassifying user intent). - Why the cross-process re-read sits between the LLM await and the append (manual wins at both in-process and on-disk layers). - Why `finalize()`'s abort tolerates a controller swap (in-flight identity check). - Why JSON-schema function calling instead of tag extraction (avoid reasoning preamble bleed; cross-provider reliability). Placed at docs/design/session-title/ alongside session-recap, compact-mode, fork-subagent, and other per-feature design docs. No sidebar index update required — the design folder is unindexed. * test(rename): pin model choice in bare /rename kebab path Addresses reviewer feedback: the bare `/rename` model selection (`config.getFastModel() ?? config.getModel()`) had no test pinning it either way. Previous tests mocked `getHistory: []`, which exits the function before the model is ever chosen, so a silent regression to either direction (always-main or always-fast) would pass CI. Two explicit cases now: - fastModel set → `generateContent` called with `model: 'qwen-turbo'`. - fastModel unset → `generateContent` called with `model: 'main-model'`. The tests intentionally mock a non-empty history so the kebab path reaches the generateContent call site instead of bailing on empty input.	2026-04-23 20:37:05 +08:00