API Testing & Observability

Claude Code: /plugin marketplace add wshobson/agents → /plugin install api-testing-observability@claude-code-workflows

An api-documenter agent and an api-mock command. Documentation covers OpenAPI 3.1 and, for event-driven systems, AsyncAPI; the distinction matters because a webhook or message contract cannot be expressed in a request and response schema. The mock server is the part worth noting. It is a FastAPI application with a state manager and a scenario manager, so a mocked endpoint can remember what an earlier call did and switch between success, failure and edge-case scenarios. Fixed-payload mocks let a client pass tests it would fail against the real service; a stateful one exposes that gap while the backend is still being written.