Design consistent, well-documented APIs across REST, GraphQL, gRPC, and CLI interfaces.
| GET | Read | Yes | | POST | Create / action | No | | PUT | Full replace | Yes | | PATCH | Partial update | Yes | | DELETE | Remove | Yes |
| 200 | Success (with body) | | 201 | Created | | 204 | Success (no body) | | 400 | Client error (validation) | | 401 | Not authenticated | | 403 | Not authorized | | 404 | Not found | | 409 | Conflict (duplicate, state mismatch) | | 422 | Unprocessable (semantically invalid) | | 500 | Server error |
Guide API design for REST, GraphQL, gRPC, and CLI interfaces. Use this skill when designing new APIs, reviewing existing API contracts, or establishing API conventions for a project. Produces consistent, well-documented API specifications. Source: s-hiraoku/synapse-a2a.