API Integration Skill

Purpose

Expert knowledge in building robust API clients with proper error handling, rate limiting, authentication, and retry logic.

Core Principles

1. Resilience - Handle failures gracefully
2. Rate Limiting - Respect API limits
3. Retry Logic - Exponential backoff
4. Circuit Breaker - Fail fast when needed
5. Security - Secure credential storage

Enforces

• REST/GraphQL client patterns
• Rate limiting and throttling
• Retry logic with exponential backoff
• Circuit breaker pattern
• Error handling and recovery
• Authentication (OAuth, API keys, JWT)
• Request/response logging
• Timeout configuration

API Client Pattern

class APIClient {
  constructor(config) {
    this.baseUrl = config.baseUrl;
    this.timeout = config.timeout || 30000;
    this.retries = config.retries || 3;
    this.circuitBreaker = new CircuitBreaker();
  }
  
  async request(endpoint, options = {}) {
    if (this.circuitBreaker.isOpen()) {
      throw new Error('Circuit breaker open');
    }
    
    for (let attempt = 1; attempt <= this.retries; attempt++) {
      try {
        const response = await fetch(
          `${this.baseUrl}${endpoint}`,
          { ...options, timeout: this.timeout }
        );
        
        if (!response.ok) {
          throw new APIError(response.status, response.statusText);
        }
        
        this.circuitBreaker.recordSuccess();
        return await response.json();
      } catch (error) {
        if (attempt === this.retries) {
          this.circuitBreaker.recordFailure();
          throw error;
        }
        await this.delay(1000 * Math.pow(2, attempt));
      }
    }
  }
}

When to Use

• Building API clients
• Integrating external services
• Handling API failures
• Rate limit management
• Authentication implementation

References

• REST API Design
• Circuit Breaker Pattern

Version: 1.0 | Last Updated: 2026-02-06 | Category: Development & Operations