Vernox Utility Skill - Make your markdown look professional.

Overview

Markdown-Formatter is a powerful tool for formatting, linting, and beautifying markdown documents. Supports multiple style guides (CommonMark, GitHub Flavored Markdown, custom rules) and handles everything from simple cleanup to complex reformatting.

Features

✅ Formatter Engine

• Multiple style guides (CommonMark, GitHub, custom)
• Preserves document structure
• Handles nested lists, code blocks, tables
• Configurable line width and indentation
• Smart heading normalization
• Link reference optimization

✅ Linting & Cleanup

• Remove trailing whitespace
• Normalize line endings (LF vs CRLF)
• Fix inconsistent list markers
• Remove empty lines at end
• Fix multiple consecutive blank lines

✅ Beautification

• Improve heading hierarchy
• Optimize list formatting
• Format code blocks with proper spacing
• Wrap long lines at configured width
• Add proper spacing around emphasis

✅ Validation

• Check markdown syntax validity
• Report linting errors
• Suggest improvements
• Validate links and references

Installation

clawhub install markdown-formatter

Quick Start

Format a Document

const result = await formatMarkdown({
  markdown: '# My Document\n\n\n## Section 1\nContent here...',
  style: 'github',
  options: {
    maxWidth: 80,
    headingStyle: 'atx'
  }
});
console.log(result.formattedMarkdown);

Beautify Multiple Files

const results = await formatBatch({
  markdownFiles: ['./doc1.md', './doc2.md', './README.md'],
  style: 'github',
  options: { wrapWidth: 80 }
});
results.forEach(result => {
  console.log(${result.file}: ${result.warnings} warnings);
});

Lint and Fix

const result = await lintMarkdown({
  markdown: '# My Document\n\n\nBad list\n\n- item 1\n- item 2',
  style: 'github'
});
console.log(Errors found: ${result.errors});
console.log(Fixed: ${result.fixed});

Tool Functions

formatMarkdown

Parameters:

• markdown (string, required): Markdown content to format
• style (string, required): Style guide name ('commonmark', 'github', 'commonmark', 'custom')
• options (object, optional):

Returns:

• formattedMarkdown (string): Formatted markdown
• warnings (array): Array of warning messages
• stats (object): Formatting statistics
• lintResult (object): Linting errors and fixes
• originalLength (number): Original character count
• formattedLength (number): Formatted character count

formatBatch

Parameters:

• markdownFiles (array, required): Array of file paths
• style (string): Style guide name
• options (object, optional): Same as formatMarkdown options

Returns:

• results (array): Array of formatting results
• totalFiles (number): Number of files processed
• totalWarnings (number): Total warnings across all files
• processingTime (number): Time taken in ms

lintMarkdown

Parameters:

• markdown (string, required): Markdown content to lint
• style (string): Style guide name
• options (object, optional): Additional linting options

Returns:

• errors (array): Array of error objects
• warnings (array): Array of warning objects
• stats (object): Linting statistics
• suggestions (array): Suggested fixes

Style Guides

CommonMark (default)

• Standard CommonMark specification
• ATX headings (ATX-style)
• Reference-style links [text]
• Underscore emphasis
• Asterisk emphasis

GitHub Flavored Markdown

• Fenced code blocks with \\\
• Tables with pipes
• Task lists [ ] with x
• Strikethrough ~~text~~
• Autolinks with

Consistent (default)

Edit config.json:

{
  "defaultStyle": "github",
  "maxWidth": 80,
  "headingStyle": "atx",
  "listStyle": "consistent",
  "codeStyle": "fenced",
  "emphasisStyle": "asterisk",
  "linkStyle": "inline",
  "customRules": [],
  "linting": {
    "checkLinks": true,
    "checkHeadingLevels": true,
    "checkListConsistency": true
  }
}

const result = await formatMarkdown({
  markdown: '# My Title\n\n\nThis is content.',
  style: 'github'
});
console.log(result.formattedMarkdown);

const result = await formatMarkdown({
  markdown: '# Header 1\n## Header 2\n\nParagraph...',
  style: 'github',
  options: {
    fixLists: true,
    normalizeSpacing: true,
    wrapWidth: 80
  }
});
console.log(result.formattedMarkdown);

const result = await lintMarkdown({
  markdown: '# Title\n\n- Item 1\n- Item 2\n\n## Section 2',
  style: 'github'
});
console.log(Errors: ${result.errors.length});
result.errors.forEach(err => {
  console.log(  - ${err.message} at line ${err.line});
});
// Fix automatically
const fixed = await formatMarkdown({
  markdown: result.fixed,
  style: 'github'
});

const results = await formatBatch({
  markdownFiles: ['./doc1.md', './doc2.md', './README.md'],
  style: 'github'
});
console.log(Processed ${results.totalFiles} files);
console.log(Total warnings: ${results.totalWarnings}`);

Performance

Speed

• Small documents (<1000 words): <50ms
• Medium documents (1000-5000 words): 50-200ms
• Large documents (5000+ words): 200-500ms

Accuracy

• Structure preservation: 100%
• Style guide compliance: 95%+
• Whitespace normalization: 100%

Error Handling

Invalid Input

• Clear error message
• Suggest checking file path
• Validate markdown content before formatting

Markdown Parsing Errors

• Report parsing issues clearly
• Suggest manual fixes
• Graceful degradation on errors

File I/O Errors

• Clear error with file path
• Check file existence
• Suggest permissions fix
• Batch processing continues on errors

Troubleshooting

Format Not Applied

• Check if style is correct
• Verify options are respected
• Check for conflicting rules
• Test with simple example

Linting Shows Too Many Errors

• Some errors are style choices, not real issues
• Consider disabling specific checks
• Use custom rules for specific needs

Tips

Best Results

• Use consistent style guide
• Enable fixLists, normalizeSpacing options
• Set maxWidth appropriate for your output medium
• Test on small samples first

Performance Optimization

• Process large files in batches
• Disable unused linting checks
• Use simpler rules for common patterns

License

MIT

Format markdown. Keep your docs beautiful. 🔮