fix: decouple stuck detector timeout

.changeset/stuck-detector-workflow-timeout.md

@@ -2,4 +2,4 @@
 "@runfusion/fusion": patch
 ---
 
-Keep stuck task detection active by falling back to the workflow step timeout when no explicit stuck timeout is configured.
+Keep stuck task detection active by default with an explicit task-stuck timeout default, without coupling it to workflow step timeout settings.

packages/core/src/__tests__/settings-parity.test.ts

@@ -69,6 +69,11 @@ describe("settings key parity", () => {
     expect(DEFAULT_PROJECT_SETTINGS.completionDocumentationMode).toBe("off");
   });
 
+  it("keeps task stuck timeout active by default without coupling to workflow step timeout", () => {
+    expect(DEFAULT_PROJECT_SETTINGS.taskStuckTimeoutMs).toBe(600_000);
+    expect(DEFAULT_PROJECT_SETTINGS.workflowStepTimeoutMs).toBe(360_000);
+  });
+
   it("keeps github tracking keys in expected scopes with documented defaults", () => {
     expect(DEFAULT_PROJECT_SETTINGS.githubTrackingEnabledByDefault).toBe(false);
     expect(DEFAULT_PROJECT_SETTINGS.githubTrackingDefaultRepo).toBeUndefined();

packages/core/src/settings-schema.ts

@@ -214,7 +214,7 @@ export const DEFAULT_PROJECT_SETTINGS = {
   requirePlanApproval: false,
   specStalenessEnabled: false,
   specStalenessMaxAgeMs: 6 * 60 * 60 * 1000,
-  taskStuckTimeoutMs: undefined,
+  taskStuckTimeoutMs: 600_000,
   aiSessionTtlMs: 7 * 24 * 60 * 60 * 1000,
   aiSessionCleanupIntervalMs: 60 * 60 * 1000,
   autoUnpauseEnabled: true,

packages/core/src/types.ts

@@ -2180,7 +2180,7 @@ export interface ProjectSettings {
   /** Timeout in milliseconds for detecting stuck tasks. When a task's agent session
    *  shows no activity (no text deltas, tool calls, or progress updates) for longer
    *  than this duration, the task is considered stuck and will be terminated and retried.
-   *  Default: undefined (disabled). Suggested value: 600000 (10 minutes). */
+   *  Default: 600000 (10 minutes). Set to 0 to disable. */
   taskStuckTimeoutMs?: number;
   /** TTL in milliseconds for persisted AI planning/subtask/mission interview sessions.
    *  Sessions older than this cutoff are expired by the dashboard session cleanup loop.

packages/engine/src/__tests__/stuck-task-detector.test.ts

@@ -718,7 +718,7 @@ describe("StuckTaskDetector", () => {
       vi.useRealTimers();
     });
 
-    it("falls back to workflow step timeout when stuck timeout is unset", async () => {
+    it("does not couple stuck detection to workflow step timeout", async () => {
       store = createMockStore({
         getSettings: vi.fn().mockResolvedValue({
           taskStuckTimeoutMs: undefined,
@@ -736,19 +736,17 @@ describe("StuckTaskDetector", () => {
 
       await customDetector.checkNow();
 
-      expect(onStuck).toHaveBeenCalledWith(
-        expect.objectContaining({ taskId: "FN-001", reason: "inactivity" }),
-      );
-      expect(session.dispose).toHaveBeenCalled();
+      expect(onStuck).not.toHaveBeenCalled();
+      expect(session.dispose).not.toHaveBeenCalled();
 
       vi.useRealTimers();
     });
 
-    it("does nothing when both stuck and workflow timeouts are disabled", async () => {
+    it("kills stuck sessions when the project default stuck timeout is present", async () => {
       store = createMockStore({
         getSettings: vi.fn().mockResolvedValue({
-          taskStuckTimeoutMs: undefined,
-          workflowStepTimeoutMs: undefined,
+          taskStuckTimeoutMs: 600_000,
+          workflowStepTimeoutMs: 60_000,
         }),
       });
       const onStuck = vi.fn();
@@ -758,12 +756,14 @@ describe("StuckTaskDetector", () => {
       customDetector.trackTask("FN-001", session);
 
       vi.useFakeTimers({ shouldAdvanceTime: true });
-      vi.advanceTimersByTime(61_000);
+      vi.advanceTimersByTime(601_000);
 
       await customDetector.checkNow();
 
-      expect(onStuck).not.toHaveBeenCalled();
-      expect(session.dispose).not.toHaveBeenCalled();
+      expect(onStuck).toHaveBeenCalledWith(
+        expect.objectContaining({ taskId: "FN-001", reason: "inactivity" }),
+      );
+      expect(session.dispose).toHaveBeenCalled();
 
       vi.useRealTimers();
     });

packages/engine/src/stuck-task-detector.ts

@@ -11,9 +11,8 @@
  * - `recordProgress(taskId)` — step transitions (in-progress, done, skipped); resets counters
  *
  * The detector polls at a configurable interval and compares timestamps against
- * `taskStuckTimeoutMs` from settings. When that explicit override is unset, the
- * detector falls back to `workflowStepTimeoutMs` so in-flight tool calls cannot
- * leave an in-progress task unmonitored by default.
+ * `taskStuckTimeoutMs` from settings. Project defaults keep this active by
+ * default while keeping workflow-step execution timeouts independent.
  */
 
 import type { TaskStore, Settings } from "@fusion/core";
@@ -472,8 +471,8 @@ export class StuckTaskDetector {
     // Defensive fallback for pause windows where lifecycle hooks haven't run yet.
     if (settings.globalPause || settings.enginePaused) return;
 
-    const timeoutMs = settings.taskStuckTimeoutMs ?? settings.workflowStepTimeoutMs;
-    if (!timeoutMs || timeoutMs <= 0) return; // Disabled only when both stuck and workflow timeouts are unset/disabled
+    const timeoutMs = settings.taskStuckTimeoutMs;
+    if (!timeoutMs || timeoutMs <= 0) return; // Disabled when task stuck timeout is explicitly unset/disabled
 
     const stuckTasks: string[] = [];