API Testing Patterns

When to use

• Verify API contracts against a real controlled service.

Not for: api-design for defining contracts; e2e-testing for UI journeys.

Steps

1. Identify protocol, contracts, authorized environment, isolated data and tooling.

2. Exercise actual requests, authentication, ownership, invalid input and lifecycle; check GraphQL transport and operation errors.

3. Test relevant pagination, concurrency and repeated requests using the contract idempotency mechanism, not tracing headers.

4. Run, inspect logs and clean only test-owned state; determine whether failures violate tests or implementation from contract evidence.

Verify

• Real service success and failure match contracts; cleanup is scoped and mock results are not labelled integration.

References

• engineering-principles.md — shared decision boundaries, scope and verification.
• references/templates/api-test-scaffold.md — REST API test scaffold template (Jest/Supertest)