fix: clear stale workspace activity indicators

src/client/src/controllers/sessionController.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, it } from "vitest";
-import { api as defaultApi, type MessagePage, type SessionInfo, type SessionStatus, type Workspace } from "../api";
+import { api as defaultApi, type MessagePage, type SessionActivity, type SessionInfo, type SessionStatus, type Workspace } from "../api";
 import { loadCachedNewSessions, markCachedNewSessionInfo, rememberCachedNewSession } from "../cachedNewSessions";
 import { initialAppState, type AppState } from "../appState";
 import { loadDraft, saveDraft } from "../promptDraftStorage";
@@ -96,6 +96,30 @@ describe("SessionController", () => {
     Object.defineProperty(globalThis, "localStorage", { value: undefined, configurable: true });
   });
 
+  it("clears stale active activity when an idle status arrives", () => {
+    const activeActivity: SessionActivity = { sessionId: oldSession.id, phase: "active", label: "running tool", at: "2026-05-15T00:00:00.000Z" };
+    let state: AppState = {
+      ...initialAppState(),
+      selectedSession: oldSession,
+      sessions: [oldSession],
+      activity: activeActivity,
+      sessionActivities: { [oldSession.id]: activeActivity },
+    };
+    const controller = new SessionController(
+      () => state,
+      (patch) => { state = { ...state, ...patch }; },
+      () => undefined,
+      undefined,
+      { socket: new FakeSocket() },
+    );
+
+    controller.applyGlobalEvent({ type: "status.update", status: status(oldSession.id) });
+
+    expect(state.activity).toBeUndefined();
+    expect(state.sessionActivities[oldSession.id]).toBeUndefined();
+    expect(state.sessionStatuses[oldSession.id]).toMatchObject({ sessionId: oldSession.id, isStreaming: false });
+  });
+
   it("recreates missing browser-cached new sessions and moves their draft", async () => {
     const storage = new MemoryStorage();
     Object.defineProperty(globalThis, "localStorage", { value: storage, configurable: true });

src/client/src/controllers/sessionController.ts

@@ -5,6 +5,7 @@ import { clearDraft, moveDraft, saveDraft } from "../promptDraftStorage";
 import { ChatTranscriptStore } from "../chatTranscriptStore";
 import { isShellInput } from "../inputModes";
 import { SessionSocket, type GlobalSessionEvent, type SessionUiEvent } from "../sessionSocket";
+import { isSessionActive } from "../../../shared/activity";
 import { InMemorySessionSelectionMemory, markSessionArchived, markSessionsArchived, selectPreferredSession, selectionAfterArchivingSession, selectionAfterArchivingSessions, shouldDeselectAfterArchivedCollapse, type SessionSelectionMemory } from "./sessionSelection";
 import type { GetState, SetState, UpdateUrl } from "./types";
 
@@ -443,9 +444,13 @@ export class SessionController {
   }
 
   private applyStatus(status: SessionStatus) {
+    const state = this.getState();
+    const clearsStaleActivity = state.sessionActivities[status.sessionId]?.phase === "active" && !isSessionActive(status);
     this.setState({
-      sessionStatuses: { ...this.getState().sessionStatuses, [status.sessionId]: status },
-      status: this.getState().selectedSession?.id === status.sessionId ? status : this.getState().status,
+      sessionStatuses: { ...state.sessionStatuses, [status.sessionId]: status },
+      ...(clearsStaleActivity ? { sessionActivities: omitSessionActivity(state.sessionActivities, status.sessionId) } : {}),
+      status: state.selectedSession?.id === status.sessionId ? status : state.status,
+      activity: state.selectedSession?.id === status.sessionId && clearsStaleActivity ? undefined : state.activity,
     });
     if (this.catchupStreamSessionId === status.sessionId && !status.isStreaming) this.finishStreamCatchup(status.sessionId);
   }
@@ -536,6 +541,10 @@ export class SessionController {
   }
 }
 
+function omitSessionActivity(activities: Record<string, SessionActivity>, sessionId: string): Record<string, SessionActivity> {
+  return Object.fromEntries(Object.entries(activities).filter(([id]) => id !== sessionId));
+}
+
 function isTranscriptEvent(event: SessionUiEvent): boolean {
   return ["message.append", "assistant.delta", "assistant.thinking.delta", "tool.start", "tool.update", "tool.end", "shell.start", "shell.chunk", "shell.end", "command.output", "session.error"].includes(event.type);
 }