diff --git a/src/test/e2e/edge-cases.test.ts b/src/test/e2e/edge-cases.test.ts
index dcd0c68..e35ed85 100644
--- a/src/test/e2e/edge-cases.test.ts
+++ b/src/test/e2e/edge-cases.test.ts
@@ -50,7 +50,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set error scenario BEFORE dispatch
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -62,7 +62,7 @@ describe('E2E Edge Cases', () => {
       harness.clearEvents();
 
       await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:spawned event emitted
       const spawnedEvents = harness.getEventsByType('agent:spawned');
@@ -89,7 +89,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set error scenario
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -99,7 +99,7 @@ describe('E2E Edge Cases', () => {
 
       await harness.dispatchManager.queue(taskAId);
       await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Task status should be 'in_progress' (not 'completed')
       const task = await harness.taskRepository.findById(taskAId);
@@ -117,7 +117,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set error scenario
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -127,7 +127,7 @@ describe('E2E Edge Cases', () => {
 
       await harness.dispatchManager.queue(taskAId);
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Get agent result - should have error
       const agentResult = await harness.agentManager.getResult(dispatchResult.agentId!);
@@ -149,7 +149,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -161,7 +161,7 @@ describe('E2E Edge Cases', () => {
       harness.clearEvents();
 
       await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:waiting event emitted
       const waitingEvents = harness.getEventsByType('agent:waiting');
@@ -182,7 +182,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -194,7 +194,7 @@ describe('E2E Edge Cases', () => {
       harness.clearEvents();
 
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify agent is in waiting_for_input status
       const agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -205,7 +205,7 @@ describe('E2E Edge Cases', () => {
 
       // Resume agent with answers map
       await harness.agentManager.resume(dispatchResult.agentId!, { q1: 'PostgreSQL' });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:resumed event emitted
       const resumedEvents = harness.getEventsByType('agent:resumed');
@@ -232,7 +232,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario
       harness.setAgentScenario(`agent-${taskAId.slice(0, 6)}`, {
@@ -247,7 +247,7 @@ describe('E2E Edge Cases', () => {
       let agent = await harness.agentManager.get(dispatchResult.agentId!);
       expect(agent?.status).toBe('running');
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // After scenario completes: waiting_for_input
       agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -260,7 +260,7 @@ describe('E2E Edge Cases', () => {
       agent = await harness.agentManager.get(dispatchResult.agentId!);
       expect(agent?.status).toBe('running');
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // After completion: idle
       agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -311,7 +311,7 @@ describe('E2E Edge Cases', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Queue Task A and block it
       await harness.dispatchManager.queue(taskAId);
diff --git a/src/test/e2e/extended-scenarios.test.ts b/src/test/e2e/extended-scenarios.test.ts
index 76d3bc7..e2c538c 100644
--- a/src/test/e2e/extended-scenarios.test.ts
+++ b/src/test/e2e/extended-scenarios.test.ts
@@ -304,7 +304,7 @@ describe('E2E Extended Scenarios', () => {
         taskId: 'placeholder-3',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue all 4 tasks
@@ -327,8 +327,8 @@ describe('E2E Extended Scenarios', () => {
       const dispatchedIds = [result1.agentId, result2.agentId, result3.agentId];
       expect(new Set(dispatchedIds).size).toBe(3);
 
-      // Use vi.runAllTimersAsync() to complete all 3 agents
-      await vi.runAllTimersAsync();
+      // Advance timers to complete all 3 agents
+      await harness.advanceTimers();
 
       // Verify: 3 agent:stopped events
       const stoppedEvents = harness.getEventsByType('agent:stopped');
@@ -343,7 +343,7 @@ describe('E2E Extended Scenarios', () => {
       const result4 = await harness.dispatchManager.dispatchNext();
       expect(result4.success).toBe(true);
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       await harness.dispatchManager.completeTask(result4.taskId!);
 
       // Verify: all 4 tasks completed in database
@@ -483,7 +483,7 @@ describe('E2E Extended Scenarios', () => {
         taskId: 'placeholder-2',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set Task X to succeed, Task Y to crash
       harness.setAgentDone(`agent-${taskXId.slice(0, 6)}`, 'Task X completed');
@@ -503,7 +503,7 @@ describe('E2E Extended Scenarios', () => {
       expect(result2.success).toBe(true);
 
       // Run timers to complete agents
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: one agent:stopped, one agent:crashed
       const stoppedEvents = harness.getEventsByType('agent:stopped');
diff --git a/src/test/e2e/happy-path.test.ts b/src/test/e2e/happy-path.test.ts
index 85d88a6..4ba36d6 100644
--- a/src/test/e2e/happy-path.test.ts
+++ b/src/test/e2e/happy-path.test.ts
@@ -42,7 +42,7 @@ describe('E2E Happy Path', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Step 1: Queue task
@@ -69,7 +69,7 @@ describe('E2E Happy Path', () => {
       expect(spawnedEvents.length).toBe(1);
 
       // Step 3: Wait for agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify agent:stopped event
       const stoppedEvents = harness.getEventsByType('agent:stopped');
@@ -102,7 +102,7 @@ describe('E2E Happy Path', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue all three tasks
@@ -130,7 +130,7 @@ describe('E2E Happy Path', () => {
       expect(dispatchResult.taskId).toBe(taskAId);
 
       // Wait for agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Complete Task A
       await harness.dispatchManager.completeTask(taskAId);
@@ -172,7 +172,7 @@ describe('E2E Happy Path', () => {
         taskId: 'placeholder-2',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue all 4 tasks
@@ -220,7 +220,7 @@ describe('E2E Happy Path', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue and dispatch task
@@ -229,7 +229,7 @@ describe('E2E Happy Path', () => {
       expect(dispatchResult.success).toBe(true);
 
       // Wait for agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Complete task
       await harness.dispatchManager.completeTask(taskAId);
@@ -289,7 +289,7 @@ describe('E2E Happy Path', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue all 5 tasks
@@ -318,7 +318,7 @@ describe('E2E Happy Path', () => {
       expect(result1.taskId).toBe(task1AId);
 
       // Wait for agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Complete Task 1A
       await harness.dispatchManager.completeTask(task1AId);
@@ -335,7 +335,7 @@ describe('E2E Happy Path', () => {
       // Task 1B (high priority among remaining)
       const result2 = await harness.dispatchManager.dispatchNext();
       expect(result2.success).toBe(true);
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       await harness.dispatchManager.completeTask(result2.taskId!);
 
       // 3 tasks remain
@@ -345,17 +345,17 @@ describe('E2E Happy Path', () => {
       // Continue dispatching remaining tasks
       const result3 = await harness.dispatchManager.dispatchNext();
       expect(result3.success).toBe(true);
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       await harness.dispatchManager.completeTask(result3.taskId!);
 
       const result4 = await harness.dispatchManager.dispatchNext();
       expect(result4.success).toBe(true);
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       await harness.dispatchManager.completeTask(result4.taskId!);
 
       const result5 = await harness.dispatchManager.dispatchNext();
       expect(result5.success).toBe(true);
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       await harness.dispatchManager.completeTask(result5.taskId!);
 
       // All tasks completed
diff --git a/src/test/e2e/recovery-scenarios.test.ts b/src/test/e2e/recovery-scenarios.test.ts
index 2f8f46e..03c2834 100644
--- a/src/test/e2e/recovery-scenarios.test.ts
+++ b/src/test/e2e/recovery-scenarios.test.ts
@@ -82,7 +82,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set crash scenario
       harness.setAgentError(`agent-${taskAId.slice(0, 6)}`, 'Token limit exceeded');
@@ -90,7 +90,7 @@ describe('E2E Recovery Scenarios', () => {
       // Queue and dispatch
       await harness.dispatchManager.queue(taskAId);
       await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify task status is 'in_progress' (not completed, not lost)
       let task = await harness.taskRepository.findById(taskAId);
@@ -104,7 +104,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Re-queue the task (it's still in_progress but we can retry)
       await harness.dispatchManager.queue(taskAId);
@@ -115,7 +115,7 @@ describe('E2E Recovery Scenarios', () => {
       // Clear events and dispatch again
       harness.clearEvents();
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent completed successfully
       expect(dispatchResult.agentId).toBeDefined();
@@ -217,7 +217,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario with options
       harness.setAgentQuestions(`agent-${taskAId.slice(0, 6)}`, [
@@ -236,7 +236,7 @@ describe('E2E Recovery Scenarios', () => {
       harness.clearEvents();
 
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:waiting event emitted
       const waitingEvents = harness.getEventsByType('agent:waiting');
@@ -248,7 +248,7 @@ describe('E2E Recovery Scenarios', () => {
       // Clear and resume with answers map
       harness.clearEvents();
       await harness.agentManager.resume(dispatchResult.agentId!, { q1: 'PostgreSQL' });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: resumed and stopped events
       const resumedEvents = harness.getEventsByType('agent:resumed');
@@ -273,7 +273,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario with options
       harness.setAgentQuestions(`agent-${taskAId.slice(0, 6)}`, [
@@ -291,7 +291,7 @@ describe('E2E Recovery Scenarios', () => {
       // Queue and dispatch
       await harness.dispatchManager.queue(taskAId);
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:waiting event has questions
       const waitingEvents = harness.getEventsByType('agent:waiting');
@@ -326,7 +326,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario
       harness.setAgentQuestions(`agent-${taskAId.slice(0, 6)}`, [
@@ -336,7 +336,7 @@ describe('E2E Recovery Scenarios', () => {
       // Queue and dispatch
       await harness.dispatchManager.queue(taskAId);
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify agent is waiting
       const agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -344,7 +344,7 @@ describe('E2E Recovery Scenarios', () => {
 
       // Resume with answers map
       await harness.agentManager.resume(dispatchResult.agentId!, { q1: 'PostgreSQL' });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent completed successfully
       const agentResult = await harness.agentManager.getResult(dispatchResult.agentId!);
@@ -368,7 +368,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Set questions scenario
       harness.setAgentQuestions(`agent-${taskAId.slice(0, 6)}`, [
@@ -383,7 +383,7 @@ describe('E2E Recovery Scenarios', () => {
       let agent = await harness.agentManager.get(dispatchResult.agentId!);
       expect(agent?.status).toBe('running');
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Phase 2: After scenario completes, waiting_for_input
       agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -400,7 +400,7 @@ describe('E2E Recovery Scenarios', () => {
       agent = await harness.agentManager.get(dispatchResult.agentId!);
       expect(agent?.status).toBe('running');
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Phase 4: After completion, idle
       agent = await harness.agentManager.get(dispatchResult.agentId!);
@@ -422,7 +422,7 @@ describe('E2E Recovery Scenarios', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Setup: agent asks two questions
       harness.setAgentQuestions(`agent-${taskAId.slice(0, 6)}`, [
@@ -443,7 +443,7 @@ describe('E2E Recovery Scenarios', () => {
       harness.clearEvents();
 
       const dispatchResult = await harness.dispatchManager.dispatchNext();
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:waiting event emitted
       const waitingEvents = harness.getEventsByType('agent:waiting');
@@ -465,7 +465,7 @@ describe('E2E Recovery Scenarios', () => {
         q1: 'SQLite',
         q2: 'Yes',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify: agent:resumed event emitted
       const resumedEvents = harness.getEventsByType('agent:resumed');
diff --git a/src/test/harness.test.ts b/src/test/harness.test.ts
index a76f7ea..3a64edf 100644
--- a/src/test/harness.test.ts
+++ b/src/test/harness.test.ts
@@ -68,7 +68,7 @@ describe('TestHarness', () => {
         prompt: 'test',
       });
 
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Verify questions array format
       const pending = await harness.getPendingQuestions(agent.id);
@@ -207,7 +207,7 @@ describe('TestHarness', () => {
         prompt: 'placeholder',
       });
       // Wait for agent to complete and become idle
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Queue the task
       await harness.dispatchManager.queue(taskAId);
@@ -219,7 +219,7 @@ describe('TestHarness', () => {
       const result = await harness.dispatchManager.dispatchNext();
 
       // Advance timers to trigger mock agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       expect(result.success).toBe(true);
       expect(result.taskId).toBe(taskAId);
@@ -264,7 +264,7 @@ describe('TestHarness', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Queue and dispatch
@@ -277,7 +277,7 @@ describe('TestHarness', () => {
       expect(spawnedEvents.length).toBe(1);
 
       // Advance timers to trigger completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Should have agent:stopped
       const stoppedEvents = harness.getEventsByType('agent:stopped');
@@ -295,7 +295,7 @@ describe('TestHarness', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Set error scenario for the agent that will be spawned
@@ -311,7 +311,7 @@ describe('TestHarness', () => {
       await harness.dispatchManager.dispatchNext();
 
       // Advance timers
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Should have agent:crashed
       const crashedEvents = harness.getEventsByType('agent:crashed');
@@ -331,7 +331,7 @@ describe('TestHarness', () => {
         taskId: 'placeholder',
         prompt: 'placeholder',
       });
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
       harness.clearEvents();
 
       // Step 1: Queue task
@@ -342,7 +342,7 @@ describe('TestHarness', () => {
       expect(dispatchResult.success).toBe(true);
 
       // Advance timers for agent completion
-      await vi.runAllTimersAsync();
+      await harness.advanceTimers();
 
       // Clear events for cleaner verification
       harness.clearEvents();
diff --git a/src/test/harness.ts b/src/test/harness.ts
index 06c3ee9..245ed78 100644
--- a/src/test/harness.ts
+++ b/src/test/harness.ts
@@ -280,6 +280,13 @@ export interface TestHarness {
    */
   advanceTimers(): Promise<void>;
 
+  /**
+   * Run a test body with fake timers enabled.
+   * Activates fake timers before the callback and restores real timers after,
+   * even if the callback throws.
+   */
+  withFakeTimers(fn: () => Promise<void>): Promise<void>;
+
   // ==========================================================================
   // Architect Mode Helpers
   // ==========================================================================
@@ -513,6 +520,15 @@ export function createTestHarness(): TestHarness {
     // Timer helper - requires vi.useFakeTimers() to be active
     advanceTimers: () => vi.runAllTimersAsync(),
 
+    withFakeTimers: async (fn: () => Promise<void>) => {
+      vi.useFakeTimers();
+      try {
+        await fn();
+      } finally {
+        vi.useRealTimers();
+      }
+    },
+
     // ========================================================================
     // Architect Mode Helpers
     // ========================================================================