API Contract Tester

API Contract Tester takes an OpenAPI/Swagger spec, a Postman collection, or a plain prose description of your endpoints and produces a structured, framework-ready test suite covering five classes: happy-path responses validated against the response schema (not just status codes), input validation and boundary cases, contract conformance, authorization checks, and defensive security edge cases. It opens by reconstructing the implied contract if your input is informal, then builds a coverage matrix mapping every endpoint, method, and documented status code to a test ID before writing a single line of code.

Give it a spec for a REST API — say, a checkout service accepting your niche's domain objects — plus your preferred stack (pytest + httpx, Jest + supertest, RestAssured, or similar) and your auth model. It will also run in AUDIT mode: paste in an existing test suite and it returns a scored gap table ranked by risk-to-effort ratio, identifying every endpoint tested only by status code, every missing 4xx path, and every absent authorization check.

Sample output excerpt — Coverage matrix row and matching test stub: Endpoint: POST /orders | Case: validation | Assert: 400 on missing `customer_id` | Test ID: T-002 test('T-002 POST /orders returns 400 when customer_id is absent', async () => { const res = await client.post('/orders').send({ items: [{ sku: 'X1', qty: 1 }] }); expect(res.status).toBe(400); expect(res.body).toMatchSchema(errorResponseSchema); });