API Design

Purpose

Design clear, consistent, and maintainable REST APIs following industry best practices and conventions.

When to Use

• Designing new API endpoints
• Refactoring existing APIs
• Creating integration interfaces
• Planning service-to-service communication

Key Capabilities

1. REST Principles - Apply RESTful design patterns correctly
2. Resource Modeling - Design clear resource hierarchies
3. Error Responses - Define consistent error handling

Approach

1. Identify resources and their relationships
2. Design URL structure (nouns, not verbs)
3. Choose appropriate HTTP methods (GET, POST, PUT, DELETE)
4. Design request/response formats
5. Plan error handling and status codes
6. Document with examples

Example

Context: User profile management API

Design:

GET    /users/{id}           # Get user
POST   /users                # Create user
PUT    /users/{id}           # Update user
DELETE /users/{id}           # Delete user
GET    /users/{id}/profile   # Get profile
PUT    /users/{id}/profile   # Update profile

Best Practices

• ✅ Use nouns for resources, HTTP verbs for actions
• ✅ Consistent URL patterns and naming
• ✅ Proper HTTP status codes (200, 201, 404, 500)
• ❌ Avoid: Verbs in URLs (/getUser, /createUser)