mermaid-validator

Validate Mermaid diagram syntax in Markdown files using a Node.js script.

3|Updated Feb 5, 2026

Search Tags:#linting #documentation #markdown #mermaid #validation #syntax #diagrams

Ready to run

npx skills add https://github.com/nano-step/skill-manager --skill mermaid-validator-nano-step

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: mermaid-validator
Source: https://github.com/nano-step/skill-manager/tree/main/skills/mermaid-validator
Command: npx skills add https://github.com/nano-step/skill-manager --skill mermaid-validator-nano-step

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Mermaid diagrams often contain syntax errors that cause render failures in documentation and UI components. This skill provides a reliable validator to catch and fix issues early, ensuring diagrams render consistently.

Core Features & Use Cases

Enforces Mermaid syntax rules to prevent common mistakes in labels, edge definitions, and node shapes.
Scans Markdown files and directories for Mermaid blocks to validate each diagram.
Useful for technical writers and developers who maintain diagrams in documentation, READMEs, and knowledge bases.

Quick Start

Run node scripts/validate-mermaid.mjs to validate all Mermaid diagrams in your project.

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 Markdown files before publishing documentation?▼

To validate Mermaid diagrams in Markdown files, run a Node.js script that scans directories for Mermaid blocks and enforces syntax rules. This catches errors in labels, edge definitions, and node shapes before documentation is published.

Why does my Mermaid diagram fail to render in documentation?▼

Mermaid diagrams fail to render due to syntax errors in labels, edge definitions, or node shapes. Validating Mermaid blocks with a dedicated scanner catches these issues early to ensure diagrams render consistently.

Do I need Node.js to check Mermaid syntax errors in my project?▼

Yes, you need Node.js to check Mermaid syntax errors. The validation process requires running a dedicated Node.js script to scan your Markdown files and enforce Mermaid syntax rules across your project.

What is the best way to scan a project directory for invalid Mermaid blocks?▼

The best way to scan a project directory for invalid Mermaid blocks is using an automated validation script. It scans all Markdown files to enforce syntax correctness and verify renderability across the entire project.

Can I check Mermaid syntax correctness for multiple Markdown files at once?▼

Yes, you can check Mermaid syntax correctness for multiple Markdown files at once. The validator scans entire directories containing Mermaid blocks to catch errors across a project before documentation is published.