REST API Design Skill

Expert assistance for designing RESTful APIs following best practices.

Capabilities

• Design resource-oriented APIs
• Implement proper HTTP methods and status codes
• Configure API versioning strategies
• Implement pagination patterns
• Design error responses
• Apply HATEOAS principles

Usage

Invoke this skill when you need to:

• Design new REST APIs
• Review existing API design
• Implement pagination
• Define error handling
• Version APIs

Design Principles

Resource Naming

# Good - nouns, plural
GET /api/users
GET /api/users/123
GET /api/users/123/posts

# Bad - verbs, actions in URL
GET /api/getUsers
GET /api/users/123/getPosts
POST /api/createUser

HTTP Methods

Method	Usage	Response
GET	Read resource	200 OK
POST	Create resource	201 Created
PUT	Replace resource	200 OK
PATCH	Partial update	200 OK
DELETE	Remove resource	204 No Content

Pagination Response

{
  "data": [...],
  "meta": {
    "page": 1,
    "limit": 10,
    "total": 100,
    "totalPages": 10
  },
  "links": {
    "self": "/api/users?page=1",
    "next": "/api/users?page=2",
    "prev": null
  }
}

Error Response

{
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Validation failed",
    "details": [
      { "field": "email", "message": "Invalid email format" }
    ]
  }
}

Best Practices

• Use proper HTTP status codes
• Implement consistent error responses
• Version APIs from the start
• Document with OpenAPI

Target Processes

• api-design
• backend-development
• microservices-architecture