api-design-and-integrationslisted

# Universal API Design & Integration Skill ## API Design Principles APIs should be: * Predictable * Versionable * Observable * Secure --- # Before Creating A New API Mandatory Questions: 1. Does an API already exist? 2. Can an existing API be extended? 3. Can frontend reuse existing response? Do not create duplicate APIs. --- # REST Standards Use: ```text GET POST PUT PATCH DELETE ``` according to intent. --- # API Response Standards Success: ```json { "data": {}, "meta": {} } ``` Failure: ```json { "errorCode": "", "message": "", "correlationId": "" } ``` --- # Pagination Standards Mandatory for list APIs. Support: * page * size * sort --- # Integration Standards External integrations must have: * Timeout * Retry policy * Circuit breaker * Monitoring Never call third-party APIs directly from business logic. --- # Integration Review Agents 1. API Architect 2. Backend Engineer 3. Security Engineer 4. Integration Engineer --- # Final Checklist ✓ Request validation ✓ Response validation ✓ Authentication ✓ Authorization ✓ Pagination ✓ Monitoring ✓ Retry handling