Claude Code Validators are a Mirdan innovation that adds an additional layer of quality assurance to Claude Code workflows. While Skills teach Claude how to do something, Validators ensure the output meets your standards before it's considered complete.
help_outlineWhy Use Validators with Claude Code?
Even with great Skills, Claude's output can sometimes:
- warningMiss edge cases or error handling
- warningSkip important security considerations
- warningForget to follow project conventions
- warningLeave TODO items or incomplete implementations
Validators act as a "second pair of eyes" - a systematic checklist that runs before work is marked complete, catching issues that might otherwise slip through to production.
psychologyHow Claude Code Validators Work
Structured Checklists
Define specific criteria that must be verified before completion
Validation Rules
Specify what to check for: security, performance, style, completeness
Automatic Remediation
When issues are found, Claude is prompted to fix them before continuing
descriptionExample validator.md File
---
name: code-reviewer
description: Validate code changes before marking complete
trigger: before-completion
---
# Code Review Validator
Run this checklist before marking any code task complete.
## Correctness
- [ ] Logic implements the requested feature correctly
- [ ] Edge cases are handled
- [ ] Error handling is present and meaningful
- [ ] No obvious bugs or regressions
## Security
- [ ] Input is validated at system boundaries
- [ ] No hardcoded secrets or credentials
- [ ] SQL queries use parameterization
- [ ] User input is sanitized for XSS
## Code Quality
- [ ] Follows project naming conventions
- [ ] No console.log or debug code left behind
- [ ] No commented-out code
- [ ] Types are correct (for TypeScript)
## Testing
- [ ] New functionality has tests
- [ ] Existing tests still pass
- [ ] Edge cases are covered
## If ANY check fails:
1. List the failing checks
2. Fix each issue
3. Re-run this validatorcompareAgent Skills vs Validators
| Aspect | Skills | Validators |
|---|---|---|
| Purpose | Teach how to do something | Verify output quality |
| When used | During task execution | Before marking complete |
| Focus | Process and workflow | Output correctness |
| Example | TDD workflow | Security checklist |
| Origin | Official Claude feature | Mirdan innovation |
build_circleHow to Create a Claude Code Validator
Identify what to validate
Think about common issues in your workflow. Security gaps? Style inconsistencies? Missing tests? These become your validation rules.
Create a validator.md file
Structure your validator with clear categories and checkboxes. Each item should be specific and actionable.
Include remediation instructions
Tell Claude what to do when a check fails. Should it fix the issue automatically? Ask for clarification? This makes validators actionable.
Test and refine
Use the validator in real workflows. Add checks for issues that slip through. Remove checks that create false positives.
Share on Mirdan.ai
Help the community catch bugs before they ship! Submit your validator to Mirdan.ai.
lightbulbPopular Validator Use Cases
Security Review
Check for common vulnerabilities, input validation, and secure coding practices.
Pre-Commit Checks
Ensure code meets quality standards before committing: no debug code, proper formatting, etc.
PR Readiness
Verify pull requests are ready for review: tests pass, docs updated, no TODOs.
Accessibility Audit
Check UI components for accessibility: ARIA labels, keyboard navigation, color contrast.
verified_userAgent Validator Protocol
The Agent Validator Protocol (AVP) is a standardized framework for validating AI agent outputs. It provides a consistent way to define validation rules, run checks, and ensure quality across AI-powered workflows.
open_in_newAgent Validator ProtocolReady to explore Claude Code Validators?
Browse our collection of community validators to improve your Claude Code workflow.
exploreBrowse Validators