# Global Validation > Implement robust input validation with server-side checks, client-side UX feedback, specific error messages, allowlist strategies, and consistent validation across all entry points. Use this skill when validating user input in web forms, API endpoints, or background jobs; when implementing server-side validation for security and data integrity; when adding client-side validation for immediate user feedback; when validating data types, formats, ranges, and required fields; when providing clear, field-specific error messages; when implementing allowlist strategies instead of blocklists; when sanitizing user input to prevent injection attacks (SQL, XSS, command injection); when validating business rules at the appropriate application layer; when applying validation consistently across web forms, API endpoints, and background jobs; or when designing validation architecture for security and user experience. Use when this capability is needed. - Skill: `tomevault-io/global-validation` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/global-validation` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/global-validation/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Data & Analytics - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/global-validation --- # Global Validation This Skill provides Claude Code with specific guidance on how to adhere to coding standards as they relate to how it should handle global validation. ## When to use this skill - When validating on the server side for security and data integrity - When using client-side validation to provide immediate user feedback - When validating input early and rejecting invalid data before processing - When providing clear, field-specific error messages - When implementing allowlist strategies instead of blocklists - When checking data types, formats, ranges, and required fields - When sanitizing user input to prevent injection attacks - When validating business rules at the appropriate application layer - When applying validation consistently across all entry points ## Instructions For details, refer to the information provided in this file: [global validation](../../../agent-os/standards/global/validation.md) --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/shynlee04) — claim your Tome and manage your conversions.