Test Agent Technical Skill

Purpose: Guide Test Agent through creating comprehensive failing test suites that serve as the living specification for features before any implementation begins.

When to use: Immediately after Architect delivers PRD + entities, before Implementer or any other agent begins work.

---

🎯 Core Mission

You create the RED phase of TDD: comprehensive test suites that FAIL appropriately, defining exactly what must be implemented. Your tests are the immutable specification—once created, they cannot be modified.

Critical principle: ALL tests must FAIL initially with "not defined" or "not implemented" errors, proving no implementation exists yet.

---

📋 6-PHASE WORKFLOW

PHASE 0: Pre-Testing Research (CRITICAL - MANDATORY)

⚠️ DO NOT SKIP THIS PHASE

Before creating ANY test files, complete this research to understand requirements and verify latest patterns.

Step 0.1: Read and Understand Requirements

# 1. Read your request from Architect
Read: PRDs/{domain}/{feature}/test-agent/00-request.md

# 2. Read master PRD for context
Read: PRDs/{domain}/{feature}/architect/00-master-prd.md

# 3. Read entities to understand data contracts
Read: app/src/features/{feature}/entities.ts

Extract from PRD:

• ✅ All user stories and acceptance criteria
• ✅ Data contracts and validation rules
• ✅ API specifications (endpoints, request/response formats)
• ✅ Business rules and edge cases
• ✅ Security requirements (RLS policies, authorization)
• ✅ Performance requirements

Step 0.2: Consult Context7 for Latest Patterns (MANDATORY)

⚠️ CRITICAL: Always verify latest testing patterns before creating tests.

// Query 1: Vitest mocking patterns
await context7.get_library_docs({
  context7CompatibleLibraryID: "/vitest-dev/vitest",
  topic: "mocking vi.mock vi.spyOn best practices",
  tokens: 2000
})

// Query 2: Playwright E2E patterns
await context7.get_library_docs({
  context7CompatibleLibraryID: "/microsoft/playwright",
  topic: "user flow testing accessibility keyboard navigation",
  tokens: 2500
})

// Query 3: Zod validation testing
await context7.get_library_docs({
  context7CompatibleLibraryID: "/colinhacks/zod",
  topic: "safeParse testing error validation",
  tokens: 2000
})

Reference files (if Context7 unavailable):

• references/vitest-patterns.md - Mocking strategies
• references/playwright-e2e-patterns.md - E2E best practices
• references/zod-testing-patterns.md - Schema validation

Step 0.3: Plan Test Coverage

Create mental map of ALL tests needed:

**Entities Layer**:
- [ ] Schema validation for all fields
- [ ] Edge cases (empty, null, undefined, wrong types)
- [ ] Refinement validations (custom rules)
- [ ] Create/Update/Query schema tests

**Use Cases Layer** (for EACH use case):
- [ ] Happy path
- [ ] Business rule validations
- [ ] Authorization checks
- [ ] Error handling
- [ ] Edge cases and boundaries

**Services Layer**:
- [ ] CRUD operations
- [ ] Query filters and pagination
- [ ] Data transformations (snake_case ↔ camelCase)
- [ ] Database error handling

**API Layer** (for EACH endpoint):
- [ ] Authentication
- [ ] Authorization
- [ ] Request validation
- [ ] Response formatting
- [ ] HTTP status codes
- [ ] Error responses

**E2E Layer**:
- [ ] Complete CRUD workflows
- [ ] Accessibility (WCAG 2.1 AA)
- [ ] Keyboard navigation
- [ ] Loading/error states

Checkpoint: Do NOT proceed to Phase 1 until you have:

• ✅ Read all requirement documents
• ✅ Consulted Context7 for latest patterns
• ✅ Mapped complete test coverage

---

PHASE 1: Create Entity Tests

File: app/src/features/{feature}/entities.test.ts

Purpose: Validate Zod schemas correctly enforce data contracts.

Step 1.1: Use Template

Start with assets/entity-test-template.ts as boilerplate.

Step 1.2: Test Main Schema

import { describe, it, expect } from 'vitest'
import { EntitySchema } from './entities'

describe('EntitySchema', () => {
  describe('valid data', () => {
    it('accepts valid complete entity', () => {
      const validEntity = {
        id: '550e8400-e29b-41d4-a716-446655440000',
        field1: 'Valid Value',
        userId: '550e8400-e29b-41d4-a716-446655440001',
        organizationId: '550e8400-e29b-41d4-a716-446655440002',
        createdAt: new Date('2024-01-01T00:00:00Z'),
        updatedAt: new Date('2024-01-02T00:00:00Z'),
      }

      const result = EntitySchema.safeParse(validEntity)

      expect(result.success).toBe(true)
      if (result.success) {
        expect(result.data).toEqual(validEntity)
      }
    })
  })

  describe('invalid data', () => {
    it('rejects entity with invalid uuid', () => {
      const invalidEntity = {
        id: 'not-a-uuid',
        // ... other fields
      }

      const result = EntitySchema.safeParse(invalidEntity)

      expect(result.success).toBe(false)
      if (!result.success) {
        expect(result.error.issues[0].validation).toBe('uuid')
      }
    })

    // Add tests for EACH validation rule from PRD
  })
})

CRITICAL: Use .safeParse() NEVER .parse() in tests.

Step 1.3: Test Derived Schemas

describe('EntityCreateSchema', () => {
  it('accepts data without auto-generated fields', () => {
    const createData = {
      field1: 'Valid Value',
      userId: 'user-id',
      organizationId: 'org-id',
      // id, createdAt, updatedAt omitted
    }

    const result = EntityCreateSchema.safeParse(createData)
    expect(result.success).toBe(true)
  })

  it('rejects data with id field', () => {
    const createData = {
      id: 'should-not-be-here',
      field1: 'Valid Value',
      // ...
    }

    const result = EntityCreateSchema.safeParse(createData)
    expect(result.success).toBe(false)
  })
})

describe('EntityUpdateSchema', () => {
  it('accepts partial data', () => {
    const updateData = { field1: 'Updated' }
    const result = EntityUpdateSchema.safeParse(updateData)
    expect(result.success).toBe(true)
  })
})

Step 1.4: Entity Test Checklist

• ✅ All schemas tested (main, Create, Update, Query)
• ✅ Valid data tests
• ✅ Invalid data tests (for EACH validation rule)
• ✅ Missing required field tests
• ✅ Min/max length tests
• ✅ Enum value tests
• ✅ UUID validation tests
• ✅ Refinement tests (custom validations)
• ✅ Uses .safeParse() everywhere
• ✅ Tests both success and error branches

Reference: See references/zod-testing-patterns.md for complete patterns.

---

PHASE 2: Create Use Case Tests

Files: app/src/features/{feature}/use-cases/{action}.test.ts

Purpose: Define expected business logic behavior (will FAIL: functions not defined).

Step 2.1: Use Template

Start with assets/use-case-test-template.ts.

Step 2.2: Configure Mocks

import { describe, it, expect, vi, beforeEach } from 'vitest'
import { createEntity } from './createEntity'
import type { EntityService } from '../services/entity.service'

// Mock the service module
vi.mock('../services/entity.service')

describe('createEntity', () => {
  let mockService: jest.Mocked<EntityService>

  beforeEach(() => {
    mockService = {
      create: vi.fn(),
      getById: vi.fn(),
      list: vi.fn(),
      update: vi.fn(),
      delete: vi.fn(),
    }
  })

  // Tests go here
})

Reference: See references/vitest-patterns.md for mocking strategies.

Step 2.3: Test Structure (for EACH use case)

describe('createEntity', () => {
  describe('happy path', () => {
    it('creates entity with valid data', async () => {
      // Arrange
      const createData = { field1: 'Test' }
      const expectedEntity = { id: 'uuid', ...createData }
      mockService.create.mockResolvedValue(expectedEntity)

      // Act
      const result = await createEntity(createData, mockService)

      // Assert
      expect(result).toEqual(expectedEntity)
      expect(mockService.create).toHaveBeenCalledWith(createData)
      expect(mockService.create).toHaveBeenCalledTimes(1)
    })
  })

  describe('validation', () => {
    it('rejects invalid data', async () => {
      const invalidData = { field1: '' } // Empty (invalid)

      await expect(
        createEntity(invalidData, mockService)
      ).rejects.toThrow('Validation failed')

      expect(mockService.create).not.toHaveBeenCalled()
    })
  })

  describe('authorization', () => {
    it('allows creation in own organization', async () => {
      // Test authorization logic
    })

    it('rejects creation in unauthorized organization', async () => {
      // Test authorization rejection
    })
  })

  describe('business rules', () => {
    it('enforces unique constraint', async () => {
      // Test business rule validation
    })
  })

  describe('error handling', () => {
    it('handles database errors', async () => {
      mockService.create.mockRejectedValue(new Error('DB error'))

      await expect(
        createEntity(createData, mockService)
      ).rejects.toThrow('Failed to create')
    })
  })

  describe('edge cases', () => {
    it('handles unicode characters', async () => {
      // Test unicode support
    })
  })
})

Step 2.4: Use Case Test Checklist (for EACH use case)

• ✅ Happy path with valid data
• ✅ Input validation (all validation rules from PRD)
• ✅ Authorization checks (user/org permissions)
• ✅ Business rules (from PRD)
• ✅ Error handling (database, network, unexpected)
• ✅ Edge cases (unicode, max lengths, boundaries)
• ✅ Service mock configured
• ✅ Service calls verified
• ✅ Service NOT called when validation fails

Reference: See references/test-structure-guide.md for Arrange-Act-Assert pattern.

---

PHASE 2.5: Create CASL Ability Tests (IF Authorization Required)

File: app/src/features/{feature}/abilities/defineAbility.test.ts

Purpose: Define authorization behavior for permission-based features (will FAIL: defineAbilitiesFor not defined).

When to include: If PRD specifies permission checks, role-based access, or Owner/Super Admin rules.

Step 2.5.1: Test Structure Template

import { describe, it, expect } from 'vitest';
import { defineAbilitiesFor } from './defineAbility';
import type { User, Workspace, Permission } from '../entities';

describe('defineAbilitiesFor', () => {
  // RED phase: This should fail initially
  it('should not be defined yet (RED phase)', () => {
    expect(defineAbilitiesFor).toBeUndefined();
  });

  // These tests will fail until Implementer creates the function
  describe('Owner bypass', () => {
    it('Owner can manage all resources', () => {
      const owner: User = {
        id: 'owner-id',
        email: 'owner@test.com',
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'owner-id',
      };

      const ability = defineAbilitiesFor({
        user: owner,
        workspace,
        permissions: [],
      });

      expect(ability.can('manage', 'all')).toBe(true);
      expect(ability.can('delete', 'Board')).toBe(true);
      expect(ability.can('create', 'Card')).toBe(true);
    });
  });

  describe('Super Admin', () => {
    it('Super Admin can manage most resources', () => {
      const superAdmin: User = {
        id: 'admin-id',
        email: 'admin@test.com',
        superAdminOrgs: ['org-id'],
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
        parent_id: 'org-id', // Part of org where user is Super Admin
      };

      const ability = defineAbilitiesFor({
        user: superAdmin,
        workspace,
        permissions: [],
      });

      expect(ability.can('manage', 'all')).toBe(true);
      expect(ability.can('read', 'Board')).toBe(true);
      expect(ability.can('update', 'Card')).toBe(true);
    });

    it('Super Admin cannot delete Organization', () => {
      const superAdmin: User = {
        id: 'admin-id',
        email: 'admin@test.com',
        superAdminOrgs: ['org-id'],
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
        parent_id: 'org-id',
      };

      const ability = defineAbilitiesFor({
        user: superAdmin,
        workspace,
        permissions: [],
      });

      expect(ability.can('delete', 'Organization')).toBe(false);
    });

    it('Super Admin cannot remove Owner permissions', () => {
      const superAdmin: User = {
        id: 'admin-id',
        email: 'admin@test.com',
        superAdminOrgs: ['org-id'],
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
        parent_id: 'org-id',
      };

      const ability = defineAbilitiesFor({
        user: superAdmin,
        workspace,
        permissions: [],
      });

      expect(ability.can('remove', 'Permission', { role: 'owner' })).toBe(false);
    });
  });

  describe('Permission-based access', () => {
    it('User with boards.create permission can create boards', () => {
      const user: User = {
        id: 'user-id',
        email: 'user@test.com',
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
      };
      const permissions: Permission[] = [
        { id: '1', full_name: 'boards.create', user_id: 'user-id' },
      ];

      const ability = defineAbilitiesFor({ user, workspace, permissions });

      expect(ability.can('create', 'Board')).toBe(true);
    });

    it('User with boards.update permission can update boards', () => {
      const user: User = {
        id: 'user-id',
        email: 'user@test.com',
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
      };
      const permissions: Permission[] = [
        { id: '1', full_name: 'boards.update', user_id: 'user-id' },
      ];

      const ability = defineAbilitiesFor({ user, workspace, permissions });

      expect(ability.can('update', 'Board')).toBe(true);
      expect(ability.can('delete', 'Board')).toBe(false); // No delete permission
    });

    it('User without permission cannot access resource', () => {
      const user: User = {
        id: 'user-id',
        email: 'user@test.com',
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
      };
      const permissions: Permission[] = []; // No permissions

      const ability = defineAbilitiesFor({ user, workspace, permissions });

      expect(ability.can('create', 'Board')).toBe(false);
      expect(ability.can('read', 'Board')).toBe(false);
      expect(ability.can('update', 'Board')).toBe(false);
      expect(ability.can('delete', 'Board')).toBe(false);
    });
  });

  describe('Conditional permissions', () => {
    it('User can only update own cards', () => {
      const user: User = {
        id: 'user-id',
        email: 'user@test.com',
      };
      const workspace: Workspace = {
        id: 'workspace-id',
        owner_id: 'different-owner-id',
      };
      const permissions: Permission[] = [
        { id: '1', full_name: 'cards.update', user_id: 'user-id', conditions: { user_id: 'user-id' } },
      ];

      const ability = defineAbilitiesFor({ user, workspace, permissions });

      expect(ability.can('update', 'Card', { user_id: 'user-id' })).toBe(true);
      expect(ability.can('update', 'Card', { user_id: 'other-user-id' })).toBe(false);
    });
  });
});

Step 2.5.2: E2E Tests for CASL Visibility

File: e2e/{feature}/authorization.spec.ts

Purpose: Verify <Can> component correctly hides/shows UI based on abilities.

import { test, expect } from '@playwright/test';

test.describe('Board authorization', () => {
  test('user without delete permission cannot see delete button', async ({ page }) => {
    // Login as user WITHOUT boards.delete permission
    await page.goto('/login');
    await page.fill('[name="email"]', 'viewer@test.com');
    await page.fill('[name="password"]', 'password');
    await page.click('button[type="submit"]');

    // Navigate to boards page
    await page.goto('/boards/123');

    // Delete button should NOT exist in DOM
    const deleteButton = page.getByRole('button', { name: /delete/i });
    await expect(deleteButton).not.toBeVisible();
  });

  test('user with delete permission sees delete button', async ({ page }) => {
    // Login as user WITH boards.delete permission
    await page.goto('/login');
    await page.fill('[name="email"]', 'editor@test.com');
    await page.fill('[name="password"]', 'password');
    await page.click('button[type="submit"]');

    // Navigate to boards page
    await page.goto('/boards/123');

    // Delete button SHOULD be visible
    const deleteButton = page.getByRole('button', { name: /delete/i });
    await expect(deleteButton).toBeVisible();
  });

  test('Owner sees all action buttons', async ({ page }) => {
    // Login as workspace Owner
    await page.goto('/login');
    await page.fill('[name="email"]', 'owner@test.com');
    await page.fill('[name="password"]', 'password');
    await page.click('button[type="submit"]');

    // Navigate to boards page
    await page.goto('/boards/123');

    // All buttons should be visible
    await expect(page.getByRole('button', { name: /create/i })).toBeVisible();
    await expect(page.getByRole('button', { name: /edit/i })).toBeVisible();
    await expect(page.getByRole('button', { name: /delete/i })).toBeVisible();
    await expect(page.getByRole('button', { name: /settings/i })).toBeVisible();
  });

  test('user without access is redirected or sees empty state', async ({ page }) => {
    // Login as user from different organization
    await page.goto('/login');
    await page.fill('[name="email"]', 'outsider@test.com');
    await page.fill('[name="password"]', 'password');
    await page.click('button[type="submit"]');

    // Try to navigate to boards page
    await page.goto('/boards/123');

    // Should redirect to 403 or show "No access" message
    await expect(page).toHaveURL(/\/(403|forbidden|no-access)/);
    // OR
    await expect(page.getByText(/you don't have access/i)).toBeVisible();
  });
});

Step 2.5.3: CASL Test Checklist

• ✅ defineAbilitiesFor() initially undefined (RED phase)
• ✅ Owner can manage 'all' resources
• ✅ Super Admin can manage 'all' with restrictions
• ✅ Super Admin cannot delete Organization
• ✅ Super Admin cannot remove Owner permissions
• ✅ User with permission can perform action
• ✅ User without permission cannot perform action
• ✅ Conditional permissions tested (if applicable)
• ✅ Field-level permissions tested (if applicable)
• ✅ E2E tests verify component visibility
• ✅ E2E tests cover all user roles (Owner, Super Admin, Editor, Viewer)
• ✅ E2E tests verify unauthorized access handling

Critical Rules:

• ❌ DON'T test CASL library itself (trust it works)
• ✅ DO test your defineAbilitiesFor() logic
• ✅ DO test that abilities match PRD requirements
• ✅ DO test Owner/Super Admin special cases
• ✅ DO verify E2E visibility matches abilities

---

PHASE 3: Create Service Tests

Files: app/src/features/{feature}/services/{entity}.service.test.ts

Purpose: Define data access behavior (will FAIL: service not defined).

Step 3.1: Use Template

Start with assets/service-test-template.ts.

Step 3.2: Mock Supabase Client

import { describe, it, expect, vi, beforeEach } from 'vitest'
import { EntityService } from './entity.service'
import type { SupabaseClient } from '@supabase/supabase-js'

const createSupabaseMock = () => {
  const selectMock = vi.fn()
  const eqMock = vi.fn()
  const singleMock = vi.fn()
  const insertMock = vi.fn()
  const updateMock = vi.fn()
  const deleteMock = vi.fn()

  const queryBuilder = {
    select: selectMock.mockReturnThis(),
    eq: eqMock.mockReturnThis(),
    single: singleMock.mockReturnThis(),
    insert: insertMock.mockReturnThis(),
    update: updateMock.mockReturnThis(),
    delete: deleteMock.mockReturnThis(),
  }

  const supabase = {
    from: vi.fn(() => queryBuilder),
    auth: { getUser: vi.fn() },
  } as unknown as SupabaseClient

  return { supabase, mocks: { selectMock, eqMock, singleMock, insertMock, updateMock, deleteMock } }
}

Reference: See references/vitest-patterns.md for Supabase mocking patterns.

Step 3.3: Test CRUD Operations

describe('EntityService', () => {
  let service: EntityService
  let supabase: SupabaseClient
  let mocks: ReturnType<typeof createSupabaseMock>['mocks']

  beforeEach(() => {
    const mockSetup = createSupabaseMock()
    supabase = mockSetup.supabase
    mocks = mockSetup.mocks
    service = new EntityService(supabase)
  })

  describe('create', () => {
    it('inserts new entity into database', async () => {
      const createData = { field1: 'Test', userId: 'user-123' }
      const createdEntity = {
        id: 'uuid',
        ...createData,
        created_at: '2024-01-01T00:00:00Z',
      }

      mocks.singleMock.mockResolvedValue({
        data: createdEntity,
        error: null,
      })

      const result = await service.create(createData)

      expect(supabase.from).toHaveBeenCalledWith('table_name')
      expect(mocks.insertMock).toHaveBeenCalledWith([{
        field1: createData.field1,
        user_id: createData.userId, // camelCase → snake_case
      }])
      expect(result).toEqual(expect.objectContaining({
        id: 'uuid',
        userId: 'user-123', // snake_case → camelCase
      }))
    })

    it('transforms snake_case from DB to camelCase', async () => {
      // Test case transformation
    })

    it('throws error when insert fails', async () => {
      mocks.singleMock.mockResolvedValue({
        data: null,
        error: { message: 'DB error', code: '23505' },
      })

      await expect(service.create(createData)).rejects.toThrow('DB error')
    })
  })

  // Similar structure for getById, list, update, delete
})

Step 3.4: Service Test Checklist

• ✅ CRUD operations tested
• ✅ snake_case ↔ camelCase transformation
• ✅ Pagination and sorting
• ✅ Filters (organizationId, userId)
• ✅ Error handling (not found, connection)
• ✅ Null return for not found (don't throw)
• ✅ Supabase client properly mocked
• ✅ Query builder chain tested
• ✅ NO business logic in tests

---

PHASE 4: Create API Route Tests

Files: app/src/app/api/{feature}/route.test.ts

Purpose: Define API behavior (will FAIL: handlers not defined).

Step 4.1: Use Template

Start with assets/api-route-test-template.ts.

Step 4.2: Mock Dependencies

import { describe, it, expect, vi, beforeEach } from 'vitest'
import { GET, POST, PATCH, DELETE } from './route'
import { NextRequest } from 'next/server'

vi.mock('@/features/{feature}/use-cases/createEntity')
vi.mock('@/lib/supabase-server')

import { createEntity } from '@/features/{feature}/use-cases/createEntity'
import { createClient } from '@/lib/supabase-server'

Step 4.3: Test API Endpoints

describe('POST /api/{feature}', () => {
  beforeEach(() => {
    vi.clearAllMocks()

    // Mock authenticated user
    vi.mocked(createClient).mockReturnValue({
      auth: {
        getUser: vi.fn().mockResolvedValue({
          data: { user: { id: 'user-123' } },
          error: null,
        }),
      },
    } as any)
  })

  describe('authentication', () => {
    it('requires authentication', async () => {
      vi.mocked(createClient).mockReturnValue({
        auth: {
          getUser: vi.fn().mockResolvedValue({
            data: { user: null },
            error: { message: 'Not authenticated' },
          }),
        },
      } as any)

      const request = new NextRequest('http://localhost:3000/api/feature', {
        method: 'POST',
        body: JSON.stringify({ field1: 'Test' }),
      })

      const response = await POST(request)

      expect(response.status).toBe(401)
      const data = await response.json()
      expect(data.error.code).toBe('UNAUTHORIZED')
    })
  })

  describe('validation', () => {
    it('validates request body with Zod', async () => {
      const invalidData = { field1: '' } // Invalid

      const request = new NextRequest('http://localhost:3000/api/feature', {
        method: 'POST',
        body: JSON.stringify(invalidData),
      })

      const response = await POST(request)

      expect(response.status).toBe(400)
      const data = await response.json()
      expect(data.error.code).toBe('VALIDATION_ERROR')
    })
  })

  describe('authorization', () => {
    it('allows creation in own organization', async () => {
      // Test authorization
    })

    it('rejects unauthorized access', async () => {
      // Test rejection
    })
  })
})

Step 4.4: API Test Checklist (for EACH endpoint)

• ✅ Authentication required (401)
• ✅ Valid request succeeds
• ✅ Invalid JSON rejected (400)
• ✅ Schema validation (400)
• ✅ Authorization checks (403)
• ✅ Not found handling (404)
• ✅ Error responses (500)
• ✅ Proper response format

---

PHASE 5: Create E2E Tests

Files: app/e2e/{feature-name}.spec.ts

Purpose: Define complete user workflows (will FAIL: no UI exists).

Step 5.1: Use Template

Start with assets/e2e-test-template.spec.ts.

Step 5.2: Test User Flows

import { test, expect } from '@playwright/test'

test.describe('{Feature} - User Flows', () => {
  test.beforeEach(async ({ page }) => {
    // Login and navigate
    await page.goto('/login')
    await page.fill('[data-testid="email"]', 'test@example.com')
    await page.fill('[data-testid="password"]', 'password123')
    await page.click('[data-testid="submit"]')
    await page.waitForURL('/dashboard')

    await page.goto('/{feature-path}')
  })

  test.describe('Create {Entity} Flow', () => {
    test('should create entity with valid data', async ({ page }) => {
      // Arrange: Open create form
      await page.click('[data-testid="create-button"]')
      await expect(page.locator('[data-testid="create-modal"]')).toBeVisible()

      // Act: Fill and submit
      await page.fill('[data-testid="field1-input"]', 'Valid Value')
      await page.click('[data-testid="submit-button"]')

      // Assert: Success feedback
      await expect(page.locator('[data-testid="success-message"]')).toBeVisible()

      // Assert: Entity in list
      await expect(page.locator('[data-testid="entity-list"]')).toContainText('Valid Value')
    })

    test('should show validation error for invalid data', async ({ page }) => {
      await page.click('[data-testid="create-button"]')
      await page.fill('[data-testid="field1-input"]', 'x') // Too short
      await page.click('[data-testid="submit-button"]')

      await expect(page.locator('[data-testid="field1-error"]')).toBeVisible()
      await expect(page.locator('[data-testid="field1-error"]')).toContainText('at least')
    })

    test('should show loading state during submission', async ({ page }) => {
      await page.click('[data-testid="create-button"]')
      await page.fill('[data-testid="field1-input"]', 'Valid')

      const submitButton = page.locator('[data-testid="submit-button"]')
      await submitButton.click()

      await expect(submitButton).toBeDisabled()
      await expect(page.locator('[data-testid="loading-spinner"]')).toBeVisible()
    })
  })

  test.describe('Accessibility', () => {
    test('should support keyboard navigation', async ({ page }) => {
      await page.locator('[data-testid="create-button"]').focus()
      await page.keyboard.press('Enter')
      await expect(page.locator('[data-testid="create-modal"]')).toBeVisible()

      await page.keyboard.press('Tab')
      await page.keyboard.type('Value 1')

      await page.keyboard.press('Escape')
      await expect(page.locator('[data-testid="create-modal"]')).not.toBeVisible()
    })

    test('should have proper ARIA labels', async ({ page }) => {
      await page.click('[data-testid="create-button"]')

      const form = page.locator('form')
      await expect(form).toHaveAttribute('aria-label', /create/i)
      await expect(page.locator('[data-testid="field1-input"]')).toHaveAttribute('aria-label')
    })
  })
})

Reference: See references/playwright-e2e-patterns.md for complete patterns.

Step 5.3: E2E Test Checklist

• ✅ All CRUD flows tested
• ✅ Validation errors shown
• ✅ Loading states tested
• ✅ Success/error messages tested
• ✅ Keyboard navigation (Tab, Enter, Esc)
• ✅ ARIA labels tested
• ✅ Focus indicators tested
• ✅ All selectors use data-testid
• ✅ Tests isolated (don't depend on each other)
• ✅ ALL tests FAIL (no UI exists)

---

PHASE 6: Validate and Document

Purpose: Verify test suite completeness and RED phase compliance.

Step 6.1: Verify All Tests FAIL

# Run unit/integration tests
npm run test

# Expected: ALL FAIL with "not defined" or "not implemented"
# ✗ use-cases/*.test.ts - FAIL (functions not defined)
# ✗ services/*.test.ts - FAIL (class not defined)
# ✗ route.test.ts - FAIL (handlers not defined)

# Run E2E tests
npm run test:e2e

# Expected: ALL FAIL (page not found / locators not found)
# ✗ e2e/{feature}.spec.ts - FAIL (no UI exists)

⚠️ CRITICAL: If ANY test passes, you've accidentally implemented code. Delete it and fix the test.

Step 6.2: Check Coverage Configuration

# Verify coverage config exists
cat vitest.config.ts

# Should have:
# coverage: {
#   provider: 'v8',
#   reporter: ['text', 'json', 'html'],
#   thresholds: {
#     lines: 90,
#     branches: 90,
#     functions: 90,
#     statements: 90
#   }
# }

npm run test:coverage
# Expected: 0% coverage (no implementation exists)

Reference: See references/coverage-validation.md for threshold configuration.

Step 6.3: Document Iteration

Create test-agent/01-iteration.md using template:

# Test Agent - Iteration 01

**Agent**: Test Agent
**Date**: YYYY-MM-DD HH:MM
**Status**: Ready for Review
**Based on**: 00-request.md

---

## Context and Scope

[What you're testing and why]

## Work Completed

### Summary

Created comprehensive failing test suite for {feature} covering:
- Entity validation (25 tests)
- Use cases (40 tests)
- Services (30 tests)
- API routes (35 tests)
- E2E flows (20 tests)

**Total**: 150 tests, all FAIL appropriately

### Detailed Breakdown

#### Entity Tests
- File: `features/{feature}/entities.test.ts`
- Tests created: 25
- Scenarios: Valid data, invalid data, refinements, Create/Update schemas

#### Use Case Tests
- Files: `features/{feature}/use-cases/*.test.ts`
- Tests created: 40
- Scenarios: Happy path, validation, authorization, business rules, errors

[Continue for all layers...]

## Technical Decisions

**Decision 1**: Mock strategy
- **Rationale**: Use vi.mock for modules, vi.spyOn for methods
- **Alternative considered**: Manual mocks
- **Why rejected**: Less type-safe, more boilerplate

[More decisions...]

## Artifacts and Deliverables

### Files Created
- `features/{feature}/entities.test.ts` (25 tests)
- `features/{feature}/use-cases/create{Entity}.test.ts` (8 tests)
- `features/{feature}/use-cases/get{Entity}.test.ts` (6 tests)
[Complete list...]

## Evidence and Validation

### Test Results

\`\`\`bash
npm run test
# Output showing ALL tests FAIL
\`\`\`

### Coverage

\`\`\`bash
npm run test:coverage
# Coverage: 0% (expected - no implementation)
\`\`\`

## Coverage Against Requirements

| Requirement from 00-request.md | Status | Evidence |
|-------------------------------|--------|----------|
| Entity validation tests | ✅ Done | entities.test.ts:1-100 |
| Use case tests | ✅ Done | use-cases/*.test.ts |
| Service tests | ✅ Done | services/*.test.ts |
| API tests | ✅ Done | api/route.test.ts |
| E2E tests | ✅ Done | e2e/{feature}.spec.ts |

## Quality Checklist

- [x] All objectives from 00-request.md met
- [x] Tests fail appropriately (not syntax errors)
- [x] Mocks configured correctly
- [x] E2E tests with accessibility requirements
- [x] >90% coverage target planned
- [x] No functional logic implemented
- [x] All tests use approved tech stack

---

## Review Status

**Submitted for Review**: YYYY-MM-DD HH:MM

### Architect Review
**Status**: Pending
**Feedback**: (Architect fills)

### User Review
**Status**: Pending
**Feedback**: (User fills)

Step 6.4: Final Validation Checklist

• ✅ ALL tests FAIL appropriately
• ✅ Coverage config set to >90%
• ✅ NO implementation code exists
• ✅ Mocks configured for all external dependencies
• ✅ E2E tests cover all user flows
• ✅ Iteration document complete
• ✅ Ready for Architect + User review

Notify completion: "Test suite iteration ready for review"

---

🚫 ANTI-PATTERNS TO AVOID

❌ DON'T: Write Tests That Pass

// ❌ WRONG: Meaningless test that passes
it('creates entity', () => {
  expect(true).toBe(true)
})

// ✅ CORRECT: Test defines behavior (will fail)
it('creates entity', async () => {
  const result = await createEntity(validData, mockService)
  expect(result).toEqual(expectedEntity)
  // FAILS: createEntity is not defined yet
})

❌ DON'T: Use .parse() in Tests

// ❌ WRONG: Throws, harder to test
it('validates', () => {
  expect(() => schema.parse(invalidData)).toThrow()
})

// ✅ CORRECT: Returns result object
it('validates', () => {
  const result = schema.safeParse(invalidData)
  expect(result.success).toBe(false)
  if (!result.success) {
    expect(result.error.issues).toHaveLength(1)
  }
})

❌ DON'T: Implement Logic in Mocks

// ❌ WRONG: Business logic in mock
vi.mock('./createEntity', () => ({
  createEntity: vi.fn(async (data) => {
    if (!data.field1) throw new Error('Required')
    return { id: 'uuid', ...data }
  })
}))

// ✅ CORRECT: Simple mock, test defines behavior
vi.mock('./createEntity')
const mockCreate = vi.mocked(createEntity)

it('validates required field', async () => {
  await expect(
    createEntity({ /* missing field1 */ }, mockService)
  ).rejects.toThrow('field1 is required')
})

---

📚 REFERENCES (Load on Demand)

When to Load References

• Creating entity tests → Load references/zod-testing-patterns.md
• Mocking dependencies → Load references/vitest-patterns.md
• Creating E2E tests → Load references/playwright-e2e-patterns.md
• Organizing tests → Load references/test-structure-guide.md
• Validating coverage → Load references/coverage-validation.md

Progressive disclosure: Don't load all upfront, load specific reference when needed.

---

✅ SUCCESS CRITERIA

Test suite is complete when:

• ✅ ALL tests FAIL appropriately (not syntax errors)
• ✅ >90% coverage target configured
• ✅ Entity tests cover all schemas and validation rules
• ✅ Use case tests cover all business logic scenarios
• ✅ Service tests cover all CRUD operations
• ✅ API tests cover all endpoints with auth/validation
• ✅ E2E tests cover all user workflows with accessibility
• ✅ Mocks configured for Supabase, use cases, auth
• ✅ Iteration documented following template
• ✅ NO implementation code exists (pure specification)

Your success is measured by: Can Implementer, Supabase Agent, and UI/UX Expert understand exactly what to build from your tests?

---

YOU ARE THE SPECIFICATION. YOUR TESTS ARE THE TRUTH.