RapidChart MCP Server

Model Context Protocol (MCP) server for RapidChart - Generate and manage diagrams directly from Cursor IDE.

Features

• 🎨 Generate diagrams from code (Class, ER, Sequence, Architecture, etc.)
• 🔄 Update existing diagrams with new code
• 📁 Organize diagrams in workspaces and folders
• 🤖 Support for multiple AI models (GPT-5, Claude, Gemini)
• 🔐 Secure Bearer token authentication
• 💳 Respects your RapidChart credits and API keys

Installation

pip install rapidchart-mcp

Or install from source:

git clone https://github.com/Samicostox/rapidchart-mcp.git
cd rapidchart-mcp
pip install -e .

Configuration

1. Generate API Token

1. Go to RapidChart Settings
2. Navigate to "API Tokens"
3. Click "Generate New Token"
4. Copy the token (starts with rc_)

2. Configure Cursor

Add to your Cursor MCP settings (~/.cursor/mcp.json or workspace .cursor/mcp.json):

{
  "mcpServers": {
    "rapidchart": {
      "command": "python",
      "args": ["-m", "rapidchart_mcp"],
      "env": {
        "RAPIDCHART_API_TOKEN": "rc_your_token_here",
        "RAPIDCHART_API_URL": "https://fastuml-0bb6938ba599.herokuapp.com",
        "RAPIDCHART_DEFAULT_TYPE": "general",
        "RAPIDCHART_FEW_PROMPTS": "false",
        "RAPIDCHART_GUIDELINES": "true"
      }
    }
  }
}

Usage

In Cursor

Once configured, you can use natural language:

User: "Generate a class diagram from src/models.py"
→ Cursor reads the file and calls RapidChart MCP
→ Returns diagram URL

User: "List my available AI models"
→ Shows models with your credit status

User: "Update diagram abc123 with new code from src/models.py"
→ Updates the diagram with context awareness

Available Tools

• list_models - Show available AI models and your credits
• list_workspaces - List your workspaces
• list_folders - List folders in a workspace
• list_diagrams - Browse your diagrams
• create_diagram - Generate diagram from code
• get_diagram - Get specific diagram details
• update_diagram - Update diagram with new code
• delete_diagram - Delete a diagram
• move_diagram - Move diagram to different folder/workspace

Environment Variables

Variable	Required	Default	Description
RAPIDCHART_API_TOKEN	✅ Yes	-	Your RapidChart API token
RAPIDCHART_API_URL	No	Production URL	API base URL
RAPIDCHART_DEFAULT_TYPE	No	general	Default diagram type
RAPIDCHART_DEFAULT_MODEL	No	Auto	Default AI model ID
RAPIDCHART_FEW_PROMPTS	No	false	Enable multi-step thinking
RAPIDCHART_GUIDELINES	No	true	Include diagram guidelines
RAPIDCHART_TIMEOUT	No	300	Request timeout (seconds)

Development

# Clone the repo
git clone https://github.com/rapidchart/rapidchart-mcp.git
cd rapidchart-mcp

# Install in development mode
pip install -e .

# Run tests
pytest

# Run the server directly
python -m rapidchart_mcp

Known Issues

503 Timeout on Diagram Creation

Symptom: You get a 503 Service Unavailable error, but the diagram is created successfully.

Cause: Heroku has a 30-second router timeout. Complex diagrams can take 30-60+ seconds to generate.

Solution:

1. The diagram IS being created despite the error
2. Run list_diagrams to see your newly created diagram
3. This is a Heroku limitation, not a bug in RapidChart

Workaround: Use simpler code or smaller diagrams for faster generation.

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License

MIT

Support

• 📧 Email: hello@rapidchart.com
• 🐛 Issues: GitHub Issues
• 📖 Docs: docs.rapidchart.com