fix(scheduled-task): scheduled task falsely reports empty assistant response due to race condition in executor polling (#127)

Author: grinev

src/scheduled-task/executor.ts

@@ -44,6 +44,7 @@ type MessagePartSnapshot = {
   text?: string;
   ignored?: boolean;
   tool?: string;
+  reason?: string;
   state?: { status?: string };
 };
 
@@ -54,6 +55,7 @@ type AssistantMessageSnapshot = {
     id?: string;
     role: string;
     summary?: unknown;
+    finish?: string;
     time?: { completed?: number };
     error?: unknown;
   };
@@ -164,7 +166,10 @@ function sleep(ms: number): Promise<void> {
 }
 
 function findLatestAssistantMessage(
-  messages: Array<{ info: { role: string; summary?: unknown }; parts: MessagePartSnapshot[] }>,
+  messages: Array<{
+    info: { role: string; summary?: unknown; finish?: string };
+    parts: MessagePartSnapshot[];
+  }>,
 ): AssistantMessageSnapshot | null {
   for (let index = messages.length - 1; index >= 0; index -= 1) {
     const message = messages[index];
@@ -176,14 +181,34 @@ function findLatestAssistantMessage(
   return null;
 }
 
+function getAssistantFinishReason(message: AssistantMessageSnapshot): string | null {
+  for (let index = message.parts.length - 1; index >= 0; index -= 1) {
+    const part = message.parts[index];
+    if (part?.type === "step-finish" && typeof part.reason === "string" && part.reason.trim()) {
+      return part.reason.trim();
+    }
+  }
+
+  if (typeof message.info.finish === "string" && message.info.finish.trim()) {
+    return message.info.finish.trim();
+  }
+
+  return null;
+}
+
 function extractAssistantResult(message: AssistantMessageSnapshot | null): {
   resultText: string | null;
   errorMessage: string | null;
   completed: boolean;
   message: AssistantMessageSnapshot | null;
 } {
   if (!message) {
-    return { resultText: null, errorMessage: null, completed: false, message: null };
+    return {
+      resultText: null,
+      errorMessage: null,
+      completed: false,
+      message: null,
+    };
   }
 
   const errorMessage = extractErrorMessage(message.info.error);
@@ -197,10 +222,14 @@ function extractAssistantResult(message: AssistantMessageSnapshot | null): {
   }
 
   const resultText = collectResponseText(message.parts);
+  const completed = Boolean(message.info.time?.completed);
+  const finishReason = getAssistantFinishReason(message);
+  const awaitingToolCalls = completed && finishReason === "tool-calls";
+
   return {
-    resultText,
+    resultText: awaitingToolCalls ? null : resultText,
     errorMessage: null,
-    completed: Boolean(message.info.time?.completed),
+    completed: completed && !awaitingToolCalls,
     message,
   };
 }
@@ -217,6 +246,7 @@ function summarizeAssistantParts(parts: MessagePartSnapshot[]): Array<{
     id: part.id,
     type: part.type,
     ignored: part.ignored,
+    reason: part.reason,
     ...(typeof part.text === "string" ? { textLength: part.text.length } : {}),
     ...(part.tool ? { tool: part.tool } : {}),
     ...(part.state?.status ? { status: part.state.status } : {}),
@@ -240,6 +270,7 @@ function logEmptyAssistantResponseDiagnostics(
           id: message.info.id,
           completed: Boolean(message.info.time?.completed),
           summary: Boolean(message.info.summary),
+          finish: getAssistantFinishReason(message),
           errorMessage: extractErrorMessage(message.info.error),
           parts: summarizeAssistantParts(message.parts),
         }

tests/scheduled-task/executor.test.ts

@@ -92,9 +92,38 @@ function createAssistantMessage(
     completed?: boolean;
     error?: unknown;
     summary?: boolean;
+    finish?: string;
+    stepFinishReason?: string;
     parts?: Array<Record<string, unknown>>;
   } = {},
 ) {
+  const generatedParts: Array<Record<string, unknown>> = [];
+  if (text) {
+    generatedParts.push({
+      id: "part-1",
+      sessionID: "session-1",
+      messageID: "assistant-1",
+      type: "text",
+      text,
+    });
+  }
+  if (options.stepFinishReason) {
+    generatedParts.push({
+      id: "finish-1",
+      sessionID: "session-1",
+      messageID: "assistant-1",
+      type: "step-finish",
+      reason: options.stepFinishReason,
+      cost: 0,
+      tokens: {
+        input: 0,
+        output: 0,
+        reasoning: 0,
+        cache: { read: 0, write: 0 },
+      },
+    });
+  }
+
   return {
     info: {
       id: "assistant-1",
@@ -118,12 +147,9 @@ function createAssistantMessage(
       },
       error: options.error,
       summary: options.summary,
+      finish: options.finish,
     },
-    parts:
-      options.parts ??
-      (text
-        ? [{ id: "part-1", sessionID: "session-1", messageID: "assistant-1", type: "text", text }]
-        : []),
+    parts: options.parts ?? generatedParts,
   };
 }
 
@@ -314,7 +340,7 @@ describe("scheduled-task/executor", () => {
     });
     mocked.promptAsyncMock.mockResolvedValueOnce({ data: undefined, error: null });
     mocked.messagesMock.mockResolvedValue({
-      data: [createAssistantMessage("", { completed: true })],
+      data: [createAssistantMessage("", { completed: true, stepFinishReason: "stop" })],
       error: null,
     });
 
@@ -341,7 +367,8 @@ describe("scheduled-task/executor", () => {
         assistantMessage: expect.objectContaining({
           completed: true,
           summary: false,
-          parts: [],
+          finish: "stop",
+          parts: [expect.objectContaining({ type: "step-finish", reason: "stop" })],
         }),
       }),
     );
@@ -391,6 +418,59 @@ describe("scheduled-task/executor", () => {
     expect(mocked.deleteMock).toHaveBeenCalledWith({ sessionID: "session-1" });
   });
 
+  it("waits for the final assistant response after completed tool-call turns", async () => {
+    const { executeScheduledTask } = await import("../../src/scheduled-task/executor.js");
+
+    const toolCallTurn = createAssistantMessage("", {
+      completed: true,
+      stepFinishReason: "tool-calls",
+    });
+
+    mocked.createMock.mockResolvedValueOnce({
+      data: { id: "session-1", directory: "D:\\Projects\\Repo", title: "Scheduled task run" },
+      error: null,
+    });
+    mocked.promptAsyncMock.mockResolvedValueOnce({ data: undefined, error: null });
+    mocked.messagesMock
+      .mockResolvedValueOnce({ data: [toolCallTurn], error: null })
+      .mockResolvedValueOnce({ data: [toolCallTurn], error: null })
+      .mockResolvedValueOnce({ data: [toolCallTurn], error: null })
+      .mockResolvedValueOnce({ data: [toolCallTurn], error: null })
+      .mockResolvedValueOnce({
+        data: [
+          toolCallTurn,
+          createAssistantMessage("SCHEDULED_TASK_FINAL_OK", {
+            completed: true,
+            stepFinishReason: "stop",
+          }),
+        ],
+        error: null,
+      });
+    mocked.statusMock.mockResolvedValue({
+      data: { "session-1": { type: "busy" } },
+      error: null,
+    });
+
+    vi.useFakeTimers();
+
+    const resultPromise = executeScheduledTask(createTask());
+
+    await vi.advanceTimersByTimeAsync(8000);
+
+    await expect(resultPromise).resolves.toMatchObject({
+      status: "success",
+      resultText: "SCHEDULED_TASK_FINAL_OK",
+      errorMessage: null,
+    });
+    expect(mocked.messagesMock).toHaveBeenCalledTimes(5);
+    expect(mocked.statusMock).toHaveBeenCalledTimes(4);
+    expect(mocked.deleteMock).toHaveBeenCalledWith({ sessionID: "session-1" });
+    expect(mocked.loggerWarnMock).not.toHaveBeenCalledWith(
+      "[ScheduledTaskExecutor] Empty completed assistant response diagnostics",
+      expect.anything(),
+    );
+  });
+
   it("ignores technical summary assistant messages when finding the scheduled task result", async () => {
     const { executeScheduledTask } = await import("../../src/scheduled-task/executor.js");