Building Better APIs: A Developer's Guide

Building a great API is like building a great tool—it should feel intuitive, powerful, and get out of your way when you need to get work done.

Core Principles

1. Consistency is King

Your API should follow predictable patterns. If you use GET /users to list users, don't suddenly switch to POST /fetch-products for products.

2. Clear Resource Naming

Use nouns, not verbs. Resources should be things, actions should be HTTP methods.

✅ GET /users/123
❌ GET /getUser/123

3. Proper HTTP Status Codes

Don't return 200 OK for everything. Use the full range of status codes meaningfully:

• 200 - Success
• 201 - Created
• 400 - Bad Request
• 401 - Unauthorized
• 404 - Not Found
• 500 - Server Error

Response Design

Structure Your Responses

Always return consistent response structures:

{
  "data": {
    /* actual data */
  },
  "meta": {
    "total": 100,
    "page": 1,
    "per_page": 20
  },
  "errors": []
}

Error Handling

Make errors actionable:

{
  "error": {
    "code": "VALIDATION_FAILED",
    "message": "The email field is required",
    "field": "email"
  }
}

Documentation

Your API is only as good as its documentation. Use tools like OpenAPI/Swagger to generate interactive docs that developers can actually use to test endpoints.

Versioning

Plan for change from day one. Use URL versioning (/v1/users) or header versioning, but be consistent and communicate changes clearly.

The best APIs feel like they were designed by someone who actually had to use them. Because they were.