diff --git a/src/test/e2e/architect-workflow.test.ts b/src/test/e2e/architect-workflow.test.ts
new file mode 100644
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+++ b/src/test/e2e/architect-workflow.test.ts
@@ -0,0 +1,102 @@
+/**
+ * E2E Tests for Architect Workflow
+ *
+ * Tests the complete architect workflow from discussion through phase creation:
+ * - Discuss mode: Gather context, answer questions, capture decisions
+ * - Breakdown mode: Decompose initiative into phases
+ * - Full workflow: Discuss -> Breakdown -> Phase persistence
+ *
+ * Uses TestHarness from src/test/ for full system wiring.
+ */
+
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
+import { createTestHarness, type TestHarness } from '../index.js';
+import type { AgentStoppedEvent } from '../../events/types.js';
+
+describe('Architect Workflow E2E', () => {
+  let harness: TestHarness;
+
+  beforeEach(() => {
+    harness = createTestHarness();
+  });
+
+  afterEach(() => {
+    harness.cleanup();
+    vi.useRealTimers();
+  });
+
+  describe('discuss mode', () => {
+    it('should spawn architect in discuss mode and complete with decisions', async () => {
+      vi.useFakeTimers();
+
+      // Create initiative
+      const initiative = await harness.createInitiative('Auth System', 'User authentication');
+
+      // Set up discuss completion scenario
+      harness.setArchitectDiscussComplete('auth-discuss', [
+        { topic: 'Auth Method', decision: 'JWT', reason: 'Stateless, scalable' },
+        { topic: 'Token Storage', decision: 'httpOnly cookie', reason: 'XSS protection' },
+      ], 'Auth approach decided');
+
+      // Spawn architect in discuss mode
+      const agent = await harness.caller.spawnArchitectDiscuss({
+        name: 'auth-discuss',
+        initiativeId: initiative.id,
+      });
+
+      expect(agent.mode).toBe('discuss');
+
+      // Wait for completion
+      await harness.advanceTimers();
+
+      // Verify agent stopped with context_complete
+      const events = harness.getEmittedEvents('agent:stopped') as AgentStoppedEvent[];
+      expect(events).toHaveLength(1);
+      expect(events[0].payload.reason).toBe('context_complete');
+    });
+
+    it('should pause on questions and resume with answers', async () => {
+      vi.useFakeTimers();
+
+      const initiative = await harness.createInitiative('Auth System');
+
+      // First, agent asks questions
+      harness.setArchitectDiscussQuestions('auth-discuss', [
+        { id: 'q1', question: 'JWT or Session?', options: [{ label: 'JWT' }, { label: 'Session' }] },
+        { id: 'q2', question: 'OAuth providers?' },
+      ]);
+
+      const agent = await harness.caller.spawnArchitectDiscuss({
+        name: 'auth-discuss',
+        initiativeId: initiative.id,
+      });
+
+      await harness.advanceTimers();
+
+      // Agent should be waiting
+      const waitingAgent = await harness.caller.getAgent({ name: 'auth-discuss' });
+      expect(waitingAgent?.status).toBe('waiting_for_input');
+
+      // Get pending questions
+      const pending = await harness.mockAgentManager.getPendingQuestions(agent.id);
+      expect(pending?.questions).toHaveLength(2);
+
+      // Now set up completion scenario for after resume
+      harness.setArchitectDiscussComplete('auth-discuss', [
+        { topic: 'Auth', decision: 'JWT', reason: 'User chose' },
+      ], 'Complete');
+
+      // Resume with answers
+      await harness.caller.resumeAgent({
+        name: 'auth-discuss',
+        answers: { q1: 'JWT', q2: 'Google, GitHub' },
+      });
+
+      await harness.advanceTimers();
+
+      // Should complete
+      const finalAgent = await harness.caller.getAgent({ name: 'auth-discuss' });
+      expect(finalAgent?.status).toBe('idle');
+    });
+  });
+});