PlantUML MCP Server

This is a Model Context Protocol (MCP) server that exposes PlantUML diagram generation functionality through the MCP protocol. It allows AI assistants and other MCP clients to generate UML diagrams from text descriptions.

Features

• Generate PlantUML diagrams in SVG or PNG format
• Validate PlantUML code with detailed error messages
• Access diagram templates for different UML diagram types
• View example diagrams
• Create diagrams from templates with customizations
• Convert text descriptions to PlantUML diagrams (basic implementation)

Prerequisites

• Python 3.8+
• PlantUML server (local or remote)
• MCP client (like Claude Desktop)

Installation

1. Install the required dependencies:

pip install -r requirements.txt

2. Set the PlantUML server URL (optional):

export PLANTUML_SERVER="http://127.0.0.1:8000/plantuml/"

By default, it uses http://127.0.0.1:8000/plantuml/ which is the local PlantUML server.

Usage

Starting the MCP Server

Run the server:

python plantuml_mcp_server.py

This will start the MCP server on port 8765 (default). You can change the port by setting the PORT environment variable:

PORT=9000 python plantuml_mcp_server.py

Connecting to the MCP Server

You can connect to the MCP server using any MCP client, such as Claude Desktop:

1. Open Claude Desktop
2. Go to Settings > MCP Servers
3. Add a new server with the URL: http://localhost:8765/sse
4. Restart Claude Desktop

Available MCP Resources

• plantuml://info - Information about the PlantUML server
• plantuml://examples - Examples of PlantUML diagrams
• plantuml://templates/{diagram_type} - Templates for specific diagram types (class, sequence, component, activity, usecase)

Available MCP Tools

• generate_diagram_base64(uml_code: str, format_type: str = "svg", timeout: int = 30) -> str - Generate a diagram from PlantUML code and return it as a base64 encoded string
• validate_plantuml(uml_code: str) -> Dict[str, Union[bool, str]] - Validate PlantUML code and return validation result with error message if any
• create_diagram_from_template(diagram_type: str, customizations: str) -> str - Create a diagram from a template with customizations
• convert_text_to_diagram(text_description: str, diagram_type: str = "class") -> Dict[str, str] - Convert a text description to a PlantUML diagram

Example Usage

Once connected to an MCP client like Claude, you can use the PlantUML server like this:

Can you create a class diagram for a simple blog system with User, Post, and Comment classes?

The AI assistant can then use the MCP server to generate the diagram and display it.

License

This project is licensed under the same license as the main PlantUML web project.