Habits that make API tests find real bugs and stay reliable — start from the contract, test every layer of a response, negative and auth tests, data ownership, schemas, environments and secrets, idempotency, contracts and mocks, CI, reporting, and a pre-merge checklist.
How to learn API testing in six milestones — explore with curl, CRUD and auth, a bug hunt with an answer key, Postman and Newman, automated tests in code, and GraphQL, security and performance — with a final project.
Copy-paste API testing reference — HTTP methods and status codes, curl flags, auth headers, the per-endpoint checklist, negative test ideas, Postman scripts, Newman, pytest/requests, Playwright request and REST Assured equivalents, GraphQL and handy one-liners.