fix(web): no "Thread completed" alert for runs a pending Monitor wakes

apps/web/src/components/ThreadNotificationCoordinator.badge.browser.test.ts

@@ -254,6 +254,53 @@ it("presents completion notifications and sound as soon as the shell completes",
   expect(state.sound).toHaveBeenCalledWith("completion", expect.any(Function));
 });
 
+it("stays quiet for runs a pending Monitor wakes and notifies when the agent finishes", async () => {
+  await using app = setup();
+  state.mode = "notifications-and-sound";
+  app.start();
+  const monitor = [{ taskId: "monitor-1", kind: "monitor" }];
+  const completedRun = (
+    ordinal: number,
+    pendingBackgroundTasks: ReadonlyArray<{ taskId: string; kind: string }>,
+  ) => {
+    const requestedAt = `2026-09-13T07:0${ordinal}:00.000Z`;
+    const raw = toV2ThreadShell({
+      ...thread,
+      latestTurn: {
+        turnId: `turn-${ordinal}`,
+        state: "completed",
+        completedAt: `2026-09-13T07:0${ordinal}:03.000Z`,
+      },
+    });
+    return {
+      status: "live",
+      snapshot: Option.some({
+        threads: [
+          {
+            ...raw,
+            latestRunRequestedAt: DateTime.makeUnsafe(requestedAt),
+            latestUserAuthoredMessageAt: SHELL_NOW,
+            pendingBackgroundTasks,
+          },
+        ],
+      }),
+    };
+  };
+  // Run 0 answers the user, runs 1-3 are Monitor wakes, run 4 is the wake after it ended.
+  state.shells.set("one", completedRun(0, monitor));
+  for (const ordinal of [1, 2, 3]) {
+    state.shells.set("one", shell());
+    state.shells.set("one", completedRun(ordinal, monitor));
+  }
+  state.shells.set("one", shell());
+  state.shells.set("one", completedRun(4, []));
+  expect(TestNotification.sent.map(({ title }) => title)).toEqual([
+    "Thread completed",
+    "Thread completed",
+  ]);
+  expect(state.sound).toHaveBeenCalledTimes(2);
+});
+
 it.each(["hasPendingApprovals", "hasPendingUserInput"] as const)(
   "notifies for offline completion and %s once across reconnects",
   async (flag) => {

apps/web/src/components/ThreadNotificationCoordinator.logic.ts

@@ -1,3 +1,6 @@
+import type { OrchestrationV2ThreadShell } from "@t3tools/contracts";
+import * as DateTime from "effect/DateTime";
+
 export type ThreadNotificationKind = "input" | "completion";
 
 export interface ThreadNotificationObservation {
@@ -45,3 +48,23 @@ export function createThreadNotificationGate<Key>(
     },
   };
 }
+
+// A Monitor wakes the agent on every event it prints. The run for each wake ends as completed
+// once the agent acknowledges the event, although the task it is monitoring has not finished.
+export function isMonitorWakeRun(
+  thread: Pick<
+    OrchestrationV2ThreadShell,
+    "latestRunRequestedAt" | "latestUserAuthoredMessageAt" | "pendingBackgroundTasks"
+  >,
+): boolean {
+  const { latestRunRequestedAt, latestUserAuthoredMessageAt } = thread;
+  // Servers without latestUserAuthoredMessageAt cannot tell a wake from the user's own run.
+  if (latestRunRequestedAt == null || latestUserAuthoredMessageAt === undefined) return false;
+  const startedByUser =
+    latestUserAuthoredMessageAt !== null &&
+    !DateTime.isGreaterThan(latestRunRequestedAt, latestUserAuthoredMessageAt);
+  const monitorPending = (thread.pendingBackgroundTasks ?? []).some(
+    (task) => task.kind === "monitor",
+  );
+  return !startedByUser && monitorPending;
+}

apps/web/src/components/ThreadNotificationCoordinator.tsx

@@ -33,6 +33,7 @@ import {
 import { resolveSidebarThreadStatus, type SidebarThreadStatus } from "./Sidebar.logic";
 import {
   createThreadNotificationGate,
+  isMonitorWakeRun,
   type ThreadNotificationKind,
   type ThreadNotificationObservation,
 } from "./ThreadNotificationCoordinator.logic";
@@ -280,7 +281,7 @@ export function startThreadNotifications(
     for (const [prior, state] of changed) {
       entry.gate.observe(state.thread.id, prior, state, {
         archived: state.thread.archivedAt !== null,
-        quiet: state.raw.latestRunStopRequested === true,
+        quiet: state.raw.latestRunStopRequested === true || isMonitorWakeRun(state.raw),
       });
     }
   };