From d82f6a602463e5c43119070646d4979c7e05d9cf Mon Sep 17 00:00:00 2001
From: YeonGyu-Kim <code.yeon.gyu@gmail.com>
Date: Tue, 12 May 2026 13:13:18 +0900
Subject: [PATCH] fix(background-agent): refresh stale todo state

---
 .../background-agent/manager.polling.test.ts  | 41 +++++++++++++++++++
 src/features/background-agent/manager.ts      |  4 +-
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/src/features/background-agent/manager.polling.test.ts b/src/features/background-agent/manager.polling.test.ts
index 3f6eb759d..bbd84d41c 100644
--- a/src/features/background-agent/manager.polling.test.ts
+++ b/src/features/background-agent/manager.polling.test.ts
@@ -345,6 +345,47 @@ describe("BackgroundManager pollRunningTasks", () => {
       expect(task.status).toBe("completed")
       expect(todoCallCount).toBe(0)
     })
+
+    test("#when cached incomplete todos become complete before idle polling #then refreshes todos and completes", async () => {
+      //#given
+      let todoCallCount = 0
+      const manager = createManagerWithClient({
+        status: async () => ({ data: { "ses-idle-stale-todos": { type: "idle" } } }),
+        todo: async () => {
+          todoCallCount += 1
+          return {
+            data: [
+              { content: "compile result", status: "completed", priority: "high" },
+            ],
+          }
+        },
+      })
+      const task = createRunningTask("ses-idle-stale-todos")
+      injectTask(manager, task)
+
+      manager.handleEvent({
+        type: "message.part.updated",
+        properties: { sessionID: "ses-idle-stale-todos", type: "text" },
+      })
+      manager.handleEvent({
+        type: "todo.updated",
+        properties: {
+          sessionID: "ses-idle-stale-todos",
+          todos: [
+            { content: "compile result", status: "in_progress", priority: "high" },
+          ],
+        },
+      })
+
+      //#when
+      const poll = manager["pollRunningTasks"]
+      await poll.call(manager)
+      manager.shutdown()
+
+      //#then
+      expect(task.status).toBe("completed")
+      expect(todoCallCount).toBe(1)
+    })
   })
 
   describe("#given a running task whose session status is busy", () => {
diff --git a/src/features/background-agent/manager.ts b/src/features/background-agent/manager.ts
index fdfa5849d..efb812eb0 100644
--- a/src/features/background-agent/manager.ts
+++ b/src/features/background-agent/manager.ts
@@ -1220,8 +1220,8 @@ The fallback retry session is now created and can be inspected directly.
 
   private async checkSessionTodos(sessionID: string): Promise<boolean> {
     const observedIncompleteTodos = this.observedIncompleteTodosBySession.get(sessionID)
-    if (observedIncompleteTodos !== undefined) {
-      return observedIncompleteTodos
+    if (observedIncompleteTodos === false) {
+      return false
     }
 
     try {