fix: generate distinct task collaboration titles

Use verified task names until Agent generates a specific conversation title.
Repair legacy names without changing manual titles or history ordering.
Bound page repairs to 30 entries and a shared two-second deadline, and
re-read titles after task access validation to avoid stale reuse receipts.

Validation: bun run check; 40 focused tests across six files.

src/routes/chatSessionRoutes.ts

@@ -14,6 +14,7 @@ import {
 import { type FrontendActionCoordinator } from "../frontendAction/coordinator.js";
 import { logger } from "../logger.js";
 import { type OpencodeRuntimeAdapter } from "../runtime/opencode.js";
+import type { ProductCredential } from "../product/server-auth-client.js";
 import {
   type SessionMetadataStore,
   type SessionRecord,
@@ -27,7 +28,7 @@ import { HistoryCursorError, historyScope, sessionHistoryPage, sessionMessagePag
 import { type LearningOrchestrator } from "../learning/orchestrator.js";
 import { toActorKey, toProjectKey } from "../utils/fileStore.js";
 import { type ChatRunState } from "./chatRunState.js";
-import { buildForkedSessionUiState } from "./chatSession.js";
+import { buildForkedSessionUiState, isGenericTaskCollaborationTitle } from "./chatSession.js";
 import { type StreamSubscriber } from "./chatUiState.js";
 import { agentTriggerContextSchema } from "./agentTrigger.js";
 import {
@@ -112,6 +113,36 @@ export const registerChatSessionRoutes = (
   const { activeRuns, lastRunStatuses } = runState;
   const getSessionRunStatus = runState.getStatus;
 
+  const refreshCollaborationTitle = async (record: SessionRecord, credential: ProductCredential | null, knownTaskTitle?: string, signal?: AbortSignal) => {
+    if (readPurpose(record) !== "task_collaboration" || !record.taskId
+      || !isGenericTaskCollaborationTitle(record.title)) return record;
+    if ((!credential && !knownTaskTitle) || signal?.aborted) return record;
+    try {
+      const state = await sessionUiStateStore.read(toSessionUiStateContext(record));
+      if (state?.isTitleManuallyEdited) return record;
+      let taskTitle = knownTaskTitle;
+      if (!taskTitle && credential) {
+        const titleSessionId = `task-title-${crypto.randomUUID()}`;
+        bindOperationalTaskCredential(titleSessionId, credential);
+        try {
+          taskTitle = (await operationalTaskClient.getAgentContext(titleSessionId, record.taskId, undefined, signal)).task.title;
+        } finally {
+          releaseOperationalTaskCredential(titleSessionId);
+          clearOperationalTaskLease(titleSessionId);
+        }
+      }
+      if (!taskTitle?.trim()) return record;
+      const latestState = await sessionUiStateStore.read(toSessionUiStateContext(record));
+      if (latestState?.isTitleManuallyEdited) return record;
+      return await sessionMetadataStore.touch(record, { title: taskTitle }, {
+        preserveUpdatedAt: true, expectedTitle: record.title ?? "",
+      });
+    } catch (error) {
+      if (!signal?.aborted) logger.warn({ err: error, sessionId: record.sessionId }, "failed to refresh task collaboration title");
+      return record;
+    }
+  };
+
   const startTaskExecution = (
     record: SessionRecord,
     credential: NonNullable<ReturnType<typeof getTrustedProductCredential>>,
@@ -321,10 +352,11 @@ export const registerChatSessionRoutes = (
       taskId.data,
       "task_collaboration",
     );
-    const validationSessionId = existing?.sessionId ?? `task-access-${crypto.randomUUID()}`;
+    const validationSessionId = `task-access-${crypto.randomUUID()}`;
+    let taskTitle: string;
     bindOperationalTaskCredential(validationSessionId, credential);
     try {
-      await operationalTaskClient.getAgentContext(validationSessionId, taskId.data);
+      taskTitle = (await operationalTaskClient.getAgentContext(validationSessionId, taskId.data)).task.title;
     } catch (error) {
       res.status(error && typeof error === "object" && "status" in error && typeof error.status === "number" ? error.status : 502).json({
         message: error instanceof Error ? error.message : "task access validation failed",
@@ -332,14 +364,19 @@ export const registerChatSessionRoutes = (
       return;
     } finally {
       releaseOperationalTaskCredential(validationSessionId);
+      clearOperationalTaskLease(validationSessionId);
     }
     if (existing) {
+      const current = await sessionMetadataStore.get(metadataContext, existing.sessionId);
+      if (!current) { res.status(404).json({ message: "session not found" }); return; }
+      const titled = await refreshCollaborationTitle(current, credential, taskTitle);
       res.json({
-        session_id: existing.sessionId,
-        purpose: readPurpose(existing),
-        task_id: existing.taskId,
+        session_id: titled.sessionId,
+        title: titled.title,
+        purpose: readPurpose(titled),
+        task_id: titled.taskId,
         created: false,
-        status: existing.status,
+        status: titled.status,
       });
       return;
     }
@@ -350,9 +387,10 @@ export const registerChatSessionRoutes = (
       purpose: "task_collaboration",
       taskId: taskId.data,
     });
-    const titled = await sessionMetadataStore.touch(record, { title: "任务协作" });
+    const titled = await sessionMetadataStore.touch(record, { title: taskTitle });
     res.status(201).json({
       session_id: titled.sessionId,
+      title: titled.title,
       purpose: readPurpose(titled),
       task_id: titled.taskId,
       created: true,
@@ -520,6 +558,15 @@ export const registerChatSessionRoutes = (
       res.status(400).json({ message: error.message });
       return;
     }
+    const credential = getTrustedProductCredential(req);
+    const titleSignal = AbortSignal.timeout(2_000);
+    const titleLimit = Math.min(page.sessions.length, 30);
+    for (let offset = 0; offset < titleLimit && !titleSignal.aborted; offset += 4) {
+      const batch = await Promise.all(page.sessions.slice(offset, Math.min(offset + 4, titleLimit)).map(async (record) => ({
+        ...record, ...await refreshCollaborationTitle(record, credential, undefined, titleSignal),
+      })));
+      page.sessions.splice(offset, batch.length, ...batch);
+    }
     res.json({
       has_more: page.has_more,
       next_cursor: page.next_cursor,
@@ -578,7 +625,7 @@ export const registerChatSessionRoutes = (
       return;
     }
 
-    const sessionRecord = await sessionMetadataStore.get(
+    let sessionRecord = await sessionMetadataStore.get(
       {
         actorKey,
         projectId,
@@ -592,6 +639,8 @@ export const registerChatSessionRoutes = (
       return;
     }
 
+    sessionRecord = await refreshCollaborationTitle(sessionRecord, getTrustedProductCredential(req));
+
     const state = await sessionUiStateStore.read(
       toSessionUiStateContext(sessionRecord),
     );