Timeout Errors (504)(Slow response from external AP)-->Reduce response time with pagination, caching, and async calls. Set a reasonable timeout. Authentication Errors (401/403](Invalid API key)-->expired token Implement token refresh logic. Use Secure Credentials Store in Appian. Bad Request Errors (400)(Incorrect request payload or missing headers Validate inputs before making API calls)--> Log request details for debugging. Server Errors (500/502/503) API server issue or downtime Implement retry mechanisms with exponential backoff. Use error messages to guide users. Parsing/Deserialization Errors Unexpected response structure Use Appian data type validation and conditional checks before processing data. Rate Limiting Errors (429) Too many requests in a short time Implement request throttling or adjust retry strategies. Use API quotas wisely.