--- name: designing-apis-8f966fa48367 description: Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation. Use when creating new APIs, designing endpoints, reviewing API contracts, or when asked about REST, GraphQL, or API patterns. --- # Designing APIs ### When to Load - **Trigger**: Designing REST or GraphQL endpoints, API contracts, versioning, request/response formats - **Skip**: Internal-only code with no API surface ## API Design Workflow Copy this checklist and track progress: ``` API Design Progress: - [ ] Step 1: Define resources and relationships - [ ] Step 2: Design endpoint structure - [ ] Step 3: Define request/response formats - [ ] Step 4: Plan error handling - [ ] Step 5: Add authentication/authorization - [ ] Step 6: Document with OpenAPI spec - [ ] Step 7: Validate design against checklist ``` ## REST API Design ### URL Structure ``` # Resource-based URLs (nouns, not verbs) GET /users # List users GET /users/:id # Get user POST /users # Create user PUT /users/:id # Replace user PATCH /users/:id # Update user DELETE /users/:id # Delete user # Nested resources GET /users/:id/orders # User's orders POST /users/:id/orders # Create order for user # Query parameters for filtering/pagination GET /users?role=admin&status=active GET /users?page=2&limit=20&sort=-createdAt ``` ### HTTP Status Codes | Code | Meaning | Use Case | | ---- | ----------------- | -------------------------- | | 200 | OK | Successful GET, PUT, PATCH | | 201 | Created | Successful POST | | 204 | No Content | Successful DELETE | | 400 | Bad Request | Invalid input | | 401 | Unauthorized | Missing/invalid auth | | 403 | Forbidden | Valid auth, no permission | | 404 | Not Found | Resource doesn't exist | | 409 | Conflict | Duplicate, state conflict | | 422 | Unprocessable | Validation failed | | 429 | Too Many Requests | Rate limited | | 500 | Internal Error | Server error | ### Response Formats **Success Response:** ```json { "data": { "id": "123", "type": "user", "attributes": { "name": "John Doe", "email": "john@example.com" } }, "meta": { "requestId": "abc-123" } } ``` **List Response with Pagination:** ```json { "data": [...], "meta": { "total": 100, "page": 1, "limit": 20, "totalPages": 5 }, "links": { "self": "/users?page=1", "next": "/users?page=2", "last": "/users?page=5" } } ``` **Error Response:** ```json { "error": { "code": "VALIDATION_ERROR", "message": "Invalid input data", "details": [ { "field": "email", "message": "Must be a valid email address" } ] }, "meta": { "requestId": "abc-123" } } ``` ## API Versioning **URL Versioning (Recommended):** ``` /api/v1/users /api/v2/users ``` **Header Versioning:** ``` Accept: application/vnd.example.v1+json ``` ## Authentication Patterns **JWT Bearer Token:** ``` Authorization: Bearer eyJhbGciOiJIUzI1NiIs... ``` **API Key:** ``` X-API-Key: your-api-key ``` ## Rate Limiting Headers ``` X-RateLimit-Limit: 100 X-RateLimit-Remaining: 95 X-RateLimit-Reset: 1609459200 Retry-After: 60 ``` ## GraphQL Patterns **Schema Design:** ```graphql # Abbreviated: input, connection and error types omitted for brevity type Query { user(id: ID!): User users(filter: UserFilter, pagination: Pagination): UserConnection! } type Mutation { createUser(input: CreateUserInput!): UserPayload! updateUser(id: ID!, input: UpdateUserInput!): UserPayload! } type User { id: ID! name: String! email: String! orders(first: Int, after: String): OrderConnection! } input CreateUserInput { name: String! email: String! } type UserPayload { user: User errors: [Error!] } ``` ## OpenAPI Specification Template See [OPENAPI-TEMPLATE.md](OPENAPI-TEMPLATE.md) for the full OpenAPI 3.0 specification template. ## API Design Validation After completing the design, validate against this checklist: ``` Validation Checklist: - [ ] All endpoints use nouns, not verbs - [ ] HTTP methods match operations correctly - [ ] Consistent response format across endpoints - [ ] Error responses include actionable details - [ ] Pagination implemented for list endpoints - [ ] Authentication defined for protected endpoints - [ ] Rate limiting headers documented - [ ] OpenAPI spec is complete and valid ``` If validation fails, return to the relevant design step and address the issues. ## Security Checklist - [ ] HTTPS only - [ ] Authentication on all endpoints - [ ] Authorization checks - [ ] Input validation - [ ] Rate limiting - [ ] Request size limits - [ ] CORS properly configured - [ ] No sensitive data in URLs - [ ] Audit logging --- Source attribution: CloudAI-X Original project: https://github.com/CloudAI-X/claude-workflow-v2 License: MIT License information: https://opensource.org/license/mit Original upstream instructions; downloaded from Mega AI Hub. ## Upstream license notice MIT License Copyright (c) 2026 Gabriel Moreira Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. # Mega AI Hub resource metadata Creator / publisher: CloudAI-X Original project: https://github.com/CloudAI-X/claude-workflow-v2 Attribution basis: Upstream repository explicitly recorded in package mirror path Fields of work: Development & Engineering, Product Management Roles: Backend Developer, Data Engineer, Growth Product Manager, Product Manager, Technical Product Manager Specialties: API, Backend, Cross Platform Tools: Tool not specified Country applicability: Country not specified Classification basis: Source catalog labels Instruction SHA-256: 7c0fa3ab2a94cc745227d4b3da766d0b7f87755942977e1021e6361d3c3aeecc