# Mermaid Validator

> Automatically validate mermaid diagrams after creating or editing them in markdown files

- Skill: `majiayu000/mermaid-validator-2` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/mermaid-validator-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/mermaid-validator-2/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Docs & Writing
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/mermaid-validator-2

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# When to Use This Skill

**Proactively use this skill after:**
- Creating new mermaid diagrams in markdown files
- Editing existing mermaid diagrams
- User asks to validate/check mermaid diagrams

**Always validate before completing the task.**

# Instructions

1. Read the markdown file (use the file from context or ask user which file to validate)
2. **Run validation** using: `mmdc -i <file-path> -o /tmp/mermaid-validation.svg 2>&1`
3. **Report validation results**:
   - If valid: Confirm the diagram is valid and exit
   - If invalid: Show the errors found and explain what's wrong
4. **Fix the issues** automatically (invalid diagrams have no value)
5. **Re-validate** to confirm the fix worked
6. Repeat steps 4-5 until there are no validation issues