# Markdownlint — Lint Markdown for AI Content Quality

> Node.js markdown linter with 50+ rules. Ensure consistent formatting in CLAUDE.md, .cursorrules, README files, and AI-generated documentation across your project.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

## Quick Use

```bash
npm install -g markdownlint-cli2
markdownlint-cli2 "**/*.md"
```

Or use the VS Code extension: search "markdownlint" in Extensions.

## What is Markdownlint?

Markdownlint is a Node.js-based linter for Markdown files with 50+ configurable rules. It catches formatting inconsistencies, broken links, and structural issues — ensuring clean, consistent markdown in your CLAUDE.md, .cursorrules, README files, and AI-generated documentation.

**Answer-Ready**: Markdownlint is a Node.js markdown linter with 50+ rules for consistent formatting. Lint CLAUDE.md, .cursorrules, README files, and AI-generated docs. Available as CLI, VS Code extension, and GitHub Action. 5k+ GitHub stars.

**Best for**: Developers maintaining markdown-based AI tool configurations. **Works with**: VS Code, JetBrains, GitHub Actions, any CI/CD. **Setup time**: Under 1 minute.

## Core Features

### 1. 50+ Built-In Rules

| Rule | Description |
|------|-------------|
| MD001 | Heading levels should increment by one |
| MD009 | No trailing spaces |
| MD013 | Line length limit |
| MD024 | No duplicate headings |
| MD032 | Lists should be surrounded by blank lines |
| MD033 | No inline HTML |
| MD041 | First line should be a top-level heading |

### 2. Configuration

```json
// .markdownlint.json
{
  "MD013": { "line_length": 120 },
  "MD033": false,
  "MD041": false,
  "MD024": { "siblings_only": true }
}
```

### 3. VS Code Integration
Install the markdownlint extension:
- Real-time linting as you type
- Quick fixes for common issues
- Works on CLAUDE.md, .cursorrules, README.md

### 4. CI/CD Integration

```yaml
# .github/workflows/lint.yml
name: Lint Markdown
on: [push, pull_request]
jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: DavidAnson/markdownlint-cli2-action@v19
        with:
          globs: "**/*.md"
```

### 5. Fix Automatically

```bash
# Auto-fix fixable issues
markdownlint-cli2 --fix "**/*.md"
```

### 6. Ignore Patterns

```
# .markdownlintignore
node_modules/
dist/
CHANGELOG.md
```

## Use with AI Tool Configs

### CLAUDE.md Linting
```bash
# Lint your Claude Code config
markdownlint-cli2 CLAUDE.md
```

### .cursorrules Linting
```bash
# Treat .cursorrules as markdown
markdownlint-cli2 .cursorrules
```

### AI-Generated Content
```bash
# Lint AI-generated docs before committing
markdownlint-cli2 --fix docs/**/*.md
```

## Common Fixes

| Issue | Fix |
|-------|-----|
| Trailing spaces | Auto-fix removes them |
| Missing blank lines | Auto-fix adds them |
| Inconsistent list markers | Auto-fix standardizes to `-` |
| Multiple blank lines | Auto-fix collapses to one |

## FAQ

**Q: Does it work with MDX?**
A: Partially — it handles standard markdown syntax. JSX blocks may trigger false positives; disable specific rules as needed.

**Q: Can I create custom rules?**
A: Yes, via the plugin API. Write rules as Node.js modules.

**Q: Is there a pre-commit hook?**
A: Yes, use with husky or lefthook for pre-commit linting.

## Source & Thanks

> Created by [David Anson](https://github.com/DavidAnson). Licensed under MIT.
>
> [DavidAnson/markdownlint](https://github.com/DavidAnson/markdownlint) — 5k+ stars

<!-- ZH -->


## Quick Start

```bash
npm install -g markdownlint-cli2
markdownlint-cli2 "**/*.md"
```

One command to check all Markdown files for formatting.

## What is Markdownlint?

A Node.js Markdown linter with 50+ rules to ensure consistent formatting. Great for CLAUDE.md, .cursorrules, README, and similar files.

**In one sentence**: Node.js Markdown linter with 50+ rules ensuring consistent formatting for CLAUDE.md, .cursorrules, and documentation — 5k+ GitHub stars.

**For**: Developers maintaining Markdown AI tool configurations.

## Core Features

### 1. 50+ Rules
Heading hierarchy, trailing whitespace, line length, duplicate headings, and more.

### 2. VS Code Integration
Real-time checks with quick fixes.

### 3. CI/CD Integration
One-click GitHub Actions configuration.

### 4. Auto-Fix
Use `--fix` to automatically fix common issues.

## FAQ

**Q: Does it support MDX?**
A: Partially — JSX may trigger false positives; disable rules as needed.

**Q: Is there a pre-commit hook?**
A: Yes — use with husky or lefthook.

## Source & Thanks

> [DavidAnson/markdownlint](https://github.com/DavidAnson/markdownlint) — 5k+ stars, MIT

---
Source: https://tokrepo.com/en/workflows/markdownlint-lint-markdown-ai-content-quality-2f24f820
Author: Script Depot