MCP FastAPI Chart Server

An MCP (Model Context Protocol) server that interacts with a FastAPI service to generate matplotlib charts.

Overview

This MCP server provides tools to:

• Generate charts using your FastAPI chart generation service
• Check the status of your FastAPI server
• Return chart images directly to the client

Prerequisites

• Python 3.8+
• Your FastAPI server running on localhost:8000 with the /plot endpoint

Installation

1. Install the package:

pip install -e .

Configuration

For Claude Desktop

Add the following to your Claude Desktop configuration file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "fastapi-chart": {
      "command": "python",
      "args": ["-m", "mcp_fastapi_chart.server"]
    }
  }
}

For Other MCP Clients

Configure your MCP client to run:

python -m mcp_fastapi_chart.server

Available Tools

1. generate_chart

Generate a chart using the FastAPI chart generation service.

Parameters:

• chart_type (string): Type of chart to generate - "line", "bar", "scatter", or "pie"
• title (string): Main title of the chart
• subtitle (string): Subtitle of the chart
• x_label (string): Label for the X-axis
• y_label (string): Label for the Y-axis
• data (object): Chart data with labels and values
• labels (array of strings): Labels for data points
• values (array of numbers): Values for data points

Example Usage:

{
  "chart_type": "line",
  "title": "Asylum Applications Trend",
  "subtitle": "Monthly applications received (2023-2024)",
  "x_label": "Month",
  "y_label": "Applications Received",
  "data": {
    "labels": ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"],
    "values": [15400, 16800, 14200, 18900, 17600, 19500, 20300, 18700, 17400, 16200, 15800, 14900]
  }
}

2. check_fastapi_status

Check if the FastAPI server is running and accessible.

Parameters: None

FastAPI Server Requirements

Your FastAPI server should have an endpoint at /plot that accepts POST requests with the following JSON structure:

{
  "chart_type": "string",
  "title": "string", 
  "subtitle": "string",
  "data": {
    "labels": ["string"],
    "values": [number]
  },
  "x_label": "string",
  "y_label": "string"
}

And should return a PNG image as the response.

Development

To run the server directly for testing:

python -m mcp_fastapi_chart.server

Cloud Deployment

When you move your FastAPI server to the cloud, update the fastapi_base_url in mcp_fastapi_chart/server.py:

self.fastapi_base_url = "https://your-cloud-domain.com"

Troubleshooting

1. Connection Errors: Make sure your FastAPI server is running on localhost:8000
2. Chart Generation Errors: Verify your FastAPI /plot endpoint is working correctly
3. MCP Connection Issues: Check your Claude Desktop configuration file syntax

License

MIT