Running Your MCP Server with FastMCP v2.0

What is Running Your MCP Server with FastMCP v2.0?

This guide explains how to run a custom MCP server using FastMCP v2.0 and install it for use with Claude Desktop. It is intended for developers who already have a server script (e.g., server.py) ready.

How to use Running Your MCP Server with FastMCP v2.0?

Install FastMCP, run the server with fastmcp run server.py (or python server.py if using the standard entry point), then install it for Claude Desktop with fastmcp install server.py and restart Claude Desktop.

Key features of Running Your MCP Server with FastMCP v2.0

• Provides fastmcp run and fastmcp install commands
• Supports specifying additional Python dependencies
• Allows passing environment variables during installation
• Supports loading environment variables from a .env file

Use cases of Running Your MCP Server with FastMCP v2.0

• Running a custom MCP server locally for development
• Integrating a custom MCP server with Claude Desktop
• Deploying a server with specific Python package dependencies

FAQ from Running Your MCP Server with FastMCP v2.0

How do I install FastMCP?

Use uv pip install fastmcp (recommended), brew install uv then uv pip install fastmcp on macOS, or pip install fastmcp.

How do I run my MCP server?

Run fastmcp run server.py. If your script uses mcp.run(), you can also run python server.py.

How do I install the server for Claude Desktop?

Run fastmcp install server.py, then restart Claude Desktop to load the server.

Can I specify additional Python dependencies?

Yes, by passing dependencies=["pandas", "numpy"] when instantiating FastMCP in your server code.

How do I set environment variables for the server?

During installation, use fastmcp install server.py -e API_KEY=your_api_key or load from a .env file with fastmcp install server.py -f .env.