fix(opencode): bind watcher sessions to app rows early

server/modules/database/repositories/sessions.db.ts

@@ -257,6 +257,43 @@ export const sessionsDb = {
     return normalizeSessionRow(row) ?? null;
   },
 
+  /**
+   * Finds the newest app-created session for a project that is still waiting
+   * for its provider-native id to be recorded.
+   *
+   * Primary intention: OpenCode can expose a new session in its shared
+   * `opencode.db` before the websocket runtime reports that same provider id
+   * back to our app. At that moment the sidebar already has an optimistic
+   * app-owned session row, but the watcher only knows the provider-native id.
+   *
+   * Without this lookup, the synchronizer would insert a second row keyed by
+   * the provider id, then `assignProviderSessionId()` would merge it a moment
+   * later. That eventually self-heals, but on slow networks the user can still
+   * briefly see two sidebar sessions for the same conversation.
+   *
+   * This helper lets the synchronizer claim the pending app row first, so the
+   * provider id is attached before any watcher-created row exists. The result
+   * is simpler than frontend dedupe and keeps the race resolved at the source.
+   */
+  findLatestPendingAppSession(provider: string, projectPath: string): SessionRow | null {
+    const db = getConnection();
+    const normalizedProjectPath = normalizeProjectPathForProvider(provider, projectPath);
+    const row = db
+      .prepare(
+        `SELECT ${SESSION_ROW_COLUMNS}
+         FROM sessions
+         WHERE provider = ?
+           AND project_path = ?
+           AND provider_session_id IS NULL
+           AND isArchived = 0
+         ORDER BY datetime(COALESCE(updated_at, created_at)) DESC, session_id DESC
+         LIMIT 1`
+      )
+      .get(provider, normalizedProjectPath) as SessionRow | undefined;
+
+    return normalizeSessionRow(row) ?? null;
+  },
+
   getAllSessions(): SessionRow[] {
     const db = getConnection();
     const rows = db

server/modules/providers/list/opencode/opencode-session-synchronizer.provider.ts

@@ -112,6 +112,17 @@ export class OpenCodeSessionSynchronizer implements IProviderSessionSynchronizer
     }
 
     const fallbackTitle = 'Untitled OpenCode Session';
+    const pendingAppSession = sessionsDb.getSessionByProviderSessionId(sessionId)
+      ?? sessionsDb.getSessionById(sessionId)
+      ?? sessionsDb.findLatestPendingAppSession(this.provider, projectPath);
+    if (pendingAppSession && !pendingAppSession.provider_session_id) {
+      // Slow networks can let the sqlite watcher index opencode.db before the
+      // runtime reports its provider id back through the websocket mapping.
+      // Bind that id to the fresh app row first so the watcher does not create
+      // a temporary provider-id sidebar entry for the same session.
+      sessionsDb.assignProviderSessionId(pendingAppSession.session_id, sessionId);
+    }
+
     // App-created sessions are keyed by an app id, so disk-discovered provider
     // ids must be resolved through the provider-id mapping first.
     const existingSession = sessionsDb.getSessionByProviderSessionId(sessionId)
@@ -123,7 +134,9 @@ export class OpenCodeSessionSynchronizer implements IProviderSessionSynchronizer
 
     // OpenCode stores every session in one shared sqlite database, so jsonl_path
     // must stay null to avoid deleting opencode.db when one app session is removed.
-    sessionsDb.createSession(
+    // Return the canonical stored row id so watcher-triggered sidebar updates
+    // stay on the app session once provider_session_id has already been mapped.
+    return sessionsDb.createSession(
       sessionId,
       this.provider,
       projectPath,
@@ -132,8 +145,6 @@ export class OpenCodeSessionSynchronizer implements IProviderSessionSynchronizer
       normalizeProviderTimestamp(row.time_updated ?? row.time_created),
       null,
     );
-
-    return sessionId;
   }
 
   private readFirstUserText(db: Database.Database, sessionId: string): string | undefined {

server/modules/providers/tests/opencode-sessions.test.ts

@@ -272,6 +272,55 @@ test('OpenCode session synchronizer indexes sqlite sessions without deletable tr
   }
 });
 
+test('OpenCode session synchronizer returns the app session id once provider mapping exists', { concurrency: false }, async () => {
+  const tempRoot = await mkdtemp(path.join(os.tmpdir(), 'opencode-session-sync-mapped-'));
+  const workspacePath = path.join(tempRoot, 'workspace');
+  await mkdir(workspacePath, { recursive: true });
+  const restoreHomeDir = patchHomeDir(tempRoot);
+
+  try {
+    await createOpenCodeDatabase(tempRoot, workspacePath);
+    await withIsolatedDatabase(() => {
+      sessionsDb.createAppSession('app-session-1', 'opencode', workspacePath);
+      sessionsDb.assignProviderSessionId('app-session-1', 'open-session-1');
+
+      const synchronizer = new OpenCodeSessionSynchronizer();
+      return synchronizer.synchronizeFile(path.join(tempRoot, '.local', 'share', 'opencode', 'opencode.db')).then((sessionId) => {
+        assert.equal(sessionId, 'app-session-1');
+        assert.equal(sessionsDb.getAllSessions().length, 1);
+        assert.equal(sessionsDb.getSessionById('app-session-1')?.provider_session_id, 'open-session-1');
+      });
+    });
+  } finally {
+    restoreHomeDir();
+    await rm(tempRoot, { recursive: true, force: true });
+  }
+});
+
+test('OpenCode session synchronizer adopts the pending app session before watcher sync creates a duplicate', { concurrency: false }, async () => {
+  const tempRoot = await mkdtemp(path.join(os.tmpdir(), 'opencode-session-sync-race-'));
+  const workspacePath = path.join(tempRoot, 'workspace');
+  await mkdir(workspacePath, { recursive: true });
+  const restoreHomeDir = patchHomeDir(tempRoot);
+
+  try {
+    await createOpenCodeDatabase(tempRoot, workspacePath);
+    await withIsolatedDatabase(() => {
+      sessionsDb.createAppSession('app-session-race', 'opencode', workspacePath);
+
+      const synchronizer = new OpenCodeSessionSynchronizer();
+      return synchronizer.synchronizeFile(path.join(tempRoot, '.local', 'share', 'opencode', 'opencode.db')).then((sessionId) => {
+        assert.equal(sessionId, 'app-session-race');
+        assert.equal(sessionsDb.getAllSessions().length, 1);
+        assert.equal(sessionsDb.getSessionById('app-session-race')?.provider_session_id, 'open-session-1');
+      });
+    });
+  } finally {
+    restoreHomeDir();
+    await rm(tempRoot, { recursive: true, force: true });
+  }
+});
+
 test('OpenCode sessions provider normalizes quoted live text and skips user echoes', () => {
   const provider = new OpenCodeSessionsProvider();
   const normalized = provider.normalizeMessage({