Unity UIToolkit MCP Server

A Vibe Coded Model Context Protocol (MCP) server that provides LLM agents with access to Unity UIToolkit documentation, code examples, and conversion tools for migrating HTML/CSS to UXML/USS.

Features

This MCP server provides the following tools for working with Unity UIToolkit:

Pre-rendered Documentation (Recommended)

• list_prerendered_docs: Lists all available pre-rendered Markdown documentation
• read_prerendered_docs: Reads clean, LLM-friendly Markdown documentation converted from Unity's HTML docs

Note: Pre-rendered documentation is automatically fetched and converted weekly via GitHub Actions using markitdown. This provides faster access, better LLM digestibility, and eliminates runtime dependencies on external sites.

Legacy Documentation Tools

• get_uitoolkit_documentation: Provides Unity UIToolkit documentation reference with links and examples for specific topics (UXML, USS, VisualElement, etc.)
• get_unity_script_reference: Access Unity Script API reference documentation for UIToolkit classes and methods
• list_uitoolkit_components: List available UIToolkit components and controls by category

Code Examples

• get_uitoolkit_code_example: Provides common Unity UIToolkit code example patterns with links to Unity's official examples repository
• fetch_unity_example_code: Fetches actual source code from Unity's UI Toolkit examples repository. Use this to retrieve implementation samples referenced in documentation (e.g., from <code source="..."/> tags)

Conversion Tools

• convert_html_to_uxml: Convert HTML markup to UXML format with guidance and best practices
• convert_css_to_uss: Convert CSS styles to USS (Unity Style Sheets) format with property mappings

Documentation Pre-rendering

Unity UIToolkit documentation is automatically fetched and converted to Markdown:

• Schedule: Weekly on Mondays at 00:00 UTC
• Trigger: Can be manually triggered via GitHub Actions
• Process:
  1. Fetches latest Unity UIToolkit HTML documentation
  2. Filters to UIToolkit-related pages only
  3. Converts to clean Markdown using markitdown
  4. Commits to docs/ directory

See .github/workflows/update-unity-docs.yml for implementation details.

Installation

npm install
npm run build

Usage

This MCP server uses the stdio transport and can be integrated with any MCP-compatible client.

Configuration

Add to your MCP client configuration (e.g., Claude Desktop config):

{
  "mcpServers": {
    "uitoolkit": {
      "command": "node",
      "args": ["/path/to/UIToolkitMCP/dist/index.js"]
    }
  }
}

Or use npx:

{
  "mcpServers": {
    "uitoolkit": {
      "command": "npx",
      "args": ["uitoolkit-mcp-server"]
    }
  }
}

Available Tools

1. list_prerendered_docs

Lists all available pre-rendered documentation files.

Parameters: None

Example:

{}

2. read_prerendered_docs

Reads pre-rendered Markdown documentation.

Parameters:

• doc_type (string): Either "manual" or "script-api"
• doc_name (string): Name of the documentation file (e.g., "UXML", "UIElements_VisualElement")

Example:

{
  "doc_type": "manual",
  "doc_name": "UXML"
}

3. get_uitoolkit_documentation

Retrieves Unity UIToolkit documentation for specific topics.

Parameters:

• topic (string): The UIToolkit topic to search for (e.g., "UXML", "USS", "VisualElement")

Example:

{
  "topic": "UXML"
}

4. get_uitoolkit_code_example

Provides common Unity UIToolkit code example patterns with links to Unity's official repository.

Parameters:

• example_name (string): Name or path of the example (e.g., "simple-list-view", "custom-control")

Example:

{
  "example_name": "simple-list-view"
}

5. fetch_unity_example_code

Fetches actual source code from Unity's UI Toolkit examples repository. This is particularly useful when you encounter <code source="..."/> tags in the script-api documentation and want to see the actual implementation.

Parameters:

• file_path (string): Path to the code file (e.g., "Button_clicked.cs" or "Modules/UIElements/Tests/UIElementsExamples/Assets/Examples/Button_clicked.cs")

Example:

{
  "file_path": "Button_clicked.cs"
}

Note: The tool will automatically search multiple Unity repositories to find the code:

• Unity's public UI Toolkit manual code examples repository
• Unity's C# Reference repository (for internal test examples)

6. get_unity_script_reference

Retrieves Unity Script API reference for UIToolkit classes.

Parameters:

• class_name (string): The Unity class name (e.g., "VisualElement", "ListView", "Button")

Example:

{
  "class_name": "ListView"
}

7. convert_html_to_uxml

Provides guidance for converting HTML to UXML.

Parameters:

• html_snippet (string): HTML code to convert

Example:

{
  "html_snippet": "<div class='container'><button>Click Me</button></div>"
}

8. convert_css_to_uss

Provides guidance for converting CSS to USS.

Parameters:

• css_snippet (string): CSS code to convert

Example:

{
  "css_snippet": ".button { background-color: blue; padding: 10px; }"
}

9. list_uitoolkit_components

Lists available UIToolkit components.

Parameters:

• category (string, optional): Filter by category ("containers", "controls", "data-bound", "advanced")

Example:

{
  "category": "controls"
}

Resources

• Unity UIToolkit Documentation
• Unity Script Reference
• Unity UIToolkit Code Examples

Development

Build

npm run build

Watch Mode

npm run watch

License

MIT