mermaid-validator

Detect and auto-correct Mermaid diagram syntax errors in Markdown files.

Updated Jan 14, 2026
One-click install
npx skills add https://github.com/sk8metalme/michi --skill mermaid-validator
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: mermaid-validator
Source: https://github.com/sk8metalme/michi/tree/main/templates/claude/skills/mermaid-validator
Command: npx skills add https://github.com/sk8metalme/michi --skill mermaid-validator

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Mermaid diagrams embedded in docs can contain syntax errors that break rendering; this skill validates and can automatically fix common mistakes, preventing parse errors during documentation generation.

Core Features & Use Cases

  • Syntax validation: Detects broken Mermaid syntax in architecture/design/sequence diagrams.
  • Format checks: Validates C4 model usage and standard Mermaid constructs.
  • Auto-corrections: Applies fixes for indentation, arrow notation, and node definitions.

Quick Start

Run the mermaid-validator skill on your docs to validate and automatically fix Mermaid diagrams (architecture.md/design.md/sequence.md and any Mermaid blocks in MD files).

Frequently Asked Questions about mermaid-validator

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I validate Mermaid diagrams in my documentation?

Mermaid diagram validation detects and fixes syntax errors in your markdown files, catching broken brackets, invalid keywords, and indentation issues before they break rendering. Run the validator on your docs/** files to automatically correct common mistakes.

Can I validate C4 model diagrams automatically?

Yes, C4 model validation checks C4Context, C4Container, and C4Component syntax along with relationship definitions. The validator ensures proper formatting and flags invalid component declarations or connection errors.

What Mermaid diagram types does this validator support?

The validator supports C4 models, sequence diagrams with participants and arrows, and graph/ER diagrams. It detects syntax errors specific to each diagram type and applies format-appropriate auto-corrections.

Do I need to manually fix Mermaid syntax errors?

No, the validator automatically corrects common issues like unclosed brackets, invalid arrow notation, and indentation problems. You can review and accept the fixes rather than finding and editing errors manually.

How do I check if my sequence diagrams are valid?

The validator scans markdown files for sequence diagram syntax, verifying participant declarations and arrow definitions. It catches missing participants, malformed arrows, and other structural errors that prevent rendering.

Can the validator work with any markdown file containing Mermaid blocks?

Yes, it validates Mermaid diagrams across architecture.md, design.md, sequence.md, and any other markdown file. The validator processes all embedded Mermaid code blocks regardless of filename.