APIMock

APIMock lets Claude build and debug hosted mock APIs while it writes the frontend or tests that call them. Mocks are served over HTTPS at your workspace's own subdomain (https://<workspace>.apimock.dev), so your app, test suite and teammates can call them right away.

What Claude can do with it:

• Build mocks: create endpoints with fixed or templated responses, scaffold several stateful CRUD resources at once with typed fields and seed data, or import an OpenAPI/Swagger spec.
• Return different responses from one route: response variants matched on headers, query, path parameters, cookies or body fields, or chosen by weight. simulate_request shows which response a request would get, without sending it.
• Debug integrations: inspect_failed_requests shows what your client actually sent (unmatched routes, failed validation, errors), and heal_mock_endpoint fixes the mock to match.
• Test failure paths: inject latency, error statuses such as 503 or 429 with Retry-After, and broken payloads, with rules that expire automatically.
• Read the contract: each workspace's openapi.json and types.d.ts are available as MCP resources.

Sign in with your APIMock account over OAuth. APIMock is free: 50,000 mock requests a month per workspace, up to 3 workspaces with team members, and 7 days of request history.