Self-Validating API Endpoint Generator

You are generating a REST API endpoint with automatic validation.

How Self-Validation Works

┌──────────────────────────────────────────────────────────────┐
│  YOUR CODE WILL BE AUTOMATICALLY VALIDATED                   │
├──────────────────────────────────────────────────────────────┤
│                                                              │
│  1. PRE-CHECK: Verify project has Express installed          │
│                                                              │
│  2. GENERATE: You create the endpoint + tests                │
│                                                              │
│  3. VALIDATE (automatic):                                    │
│     ├─ npm test → Must pass                                  │
│     ├─ npm run lint → Auto-fixed if needed                   │
│     └─ tsc --noEmit → Must type-check                        │
│                                                              │
│  4. If validation fails:                                     │
│     └─ You get feedback and retry (max 3 times)              │
│                                                              │
│  5. If still failing after 3 attempts:                       │
│     └─ Pause for human review                                │
│                                                              │
└──────────────────────────────────────────────────────────────┘

Required Outputs

1. API Endpoint (src/routes/[name].ts)

import { Router, Request, Response } from 'express';

const router = Router();

// GET /api/[name]
router.get('/', async (req: Request, res: Response) => {
  // Implementation
});

// POST /api/[name]
router.post('/', async (req: Request, res: Response) => {
  // Implementation with validation
});

export default router;

2. Test File (src/routes/[name].test.ts) – REQUIRED!

import { describe, it, expect, beforeAll, afterAll } from 'vitest';
import request from 'supertest';
import app from '../app';

describe('[Name] API', () => {
  describe('GET /api/[name]', () => {
    it('should return 200 with data', async () => {
      const res = await request(app).get('/api/[name]');
      expect(res.status).toBe(200);
      expect(res.body).toBeDefined();
    });
  });

  describe('POST /api/[name]', () => {
    it('should create resource with valid data', async () => {
      const res = await request(app)
        .post('/api/[name]')
        .send({ /* valid data */ });
      expect(res.status).toBe(201);
    });

    it('should return 400 for invalid data', async () => {
      const res = await request(app)
        .post('/api/[name]')
        .send({ /* invalid data */ });
      expect(res.status).toBe(400);
    });
  });
});

Validation Criteria

Self-Healing Behavior

If tests fail, you will receive:

1. The test output showing which tests failed
2. A request to fix the failing tests
3. Another attempt (up to 3 total)

Example failure feedback:

🔴 VALIDATION FAILED (attempt 1/3)

Test Results:
  ✗ GET /api/users should return 200 with data
    Expected: 200
    Received: 404

Please fix the route handler and regenerate.

Important Notes

1. Always generate tests – The skill will NOT complete without passing tests
2. Use proper types – TypeScript errors block completion
3. Follow lint rules – Auto-fixed but avoid common issues
4. Handle edge cases – Test both success and error paths