Global Validation

Implement comprehensive input validation on both client and server sides with clear error feedback. Use this skill when validating user input in forms, API endpoints, or data processing. Use this skill when implementing server-side validation to ensure data integrity and security. Use this skill when adding client-side validation for immediate user feedback. Use this skill when sanitizing input to prevent injection attacks. Use this skill when validating data types, formats, ranges, and business rules. Use this skill when providing specific, actionable error messages for validation failures. Use this skill when applying validation consistently across all application entry points.