Documentation Best Practices

Great API documentation is the difference between an API developers love and one they avoid. Let's learn how to document APIs effectively.

Why Documentation Matters

• Adoption: Good docs = more users
• Support: Reduces support burden
• Self-Service: Developers can onboard themselves
• Trust: Shows professionalism and stability

Essential Documentation Components

1. Getting Started Guide

# Quick Start

## 1. Get Your API Key
Sign up at https://api.example.com/signup

## 2. Make Your First Request
curl -X GET https://api.example.com/v1/users \
  -H "Authorization: Bearer YOUR_API_KEY"

## 3. Explore the API
Check out our interactive documentation...

2. Authentication Section

# Authentication

All API requests require a Bearer token:

\`\`\`http
Authorization: Bearer sk_live_abc123...
\`\`\`

Tokens can be obtained from your dashboard.

3. Endpoint Reference

## List Users

\`GET /api/v1/users\`

Returns a paginated list of users.

### Parameters

| Name | Type | Required | Description |
|------|------|----------|-------------|
| page | integer | No | Page number (default: 1) |
| limit | integer | No | Items per page (default: 20, max: 100) |

### Response

\`\`\`json
{
  "data": [...],
  "meta": { "total": 150, "page": 1 }
}
\`\`\`

4. Code Examples

### JavaScript

\`\`\`javascript
const response = await fetch('https://api.example.com/v1/users', {
  headers: {
    'Authorization': 'Bearer ' + apiKey
  }
});
const users = await response.json();
\`\`\`

### Python

\`\`\`python
import requests

response = requests.get(
    'https://api.example.com/v1/users',
    headers={'Authorization': f'Bearer {api_key}'}
)
users = response.json()
\`\`\`

5. Error Reference

# Errors

## Error Format

\`\`\`json
{
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Invalid input",
    "details": [...]
  }
}
\`\`\`

## Common Errors

| Code | HTTP Status | Description |
|------|-------------|-------------|
| VALIDATION_ERROR | 422 | Invalid request data |
| UNAUTHORIZED | 401 | Invalid or missing token |
| NOT_FOUND | 404 | Resource doesn't exist |

Exercise: Document an Endpoint

Documentation Tools

Static Documentation

• ReadMe.io - Hosted docs with analytics
• Docusaurus - React-based static site
• GitBook - Collaborative documentation
• Slate - Single-page API docs

Interactive Documentation

• Swagger UI - OpenAPI visualization
• Redoc - Beautiful OpenAPI docs
• Stoplight - API design and docs

Best Practices

1. Keep it current - Update docs with code changes
2. Include examples - Every endpoint needs examples
3. Show errors - Document what can go wrong
4. Multiple languages - Code samples in popular languages
5. Test your docs - Examples should actually work
6. Get feedback - Let developers rate helpfulness

Summary

Good documentation includes:

• Quick start guide
• Authentication details
• Complete endpoint reference
• Code examples
• Error documentation
• Changelog