This integration focuses on running local FastMCP server files with STDIO transport. For remote servers running with HTTP or SSE transport, use your client's native configuration - FastMCP's integrations focus on simplifying the complex local setup with dependencies and
uv
commands.Requirements
This integration uses STDIO transport to run your FastMCP server locally. For remote deployments, you can run your FastMCP server with HTTP or SSE transport and configure it directly using Claude Code’s built-in MCP management commands.Create a Server
The examples in this guide will use the following simple dice-rolling server, saved asserver.py
.
server.py
Install the Server
FastMCP CLI
New in version: 2.10.3
The easiest way to install a FastMCP server in Claude Code is using the fastmcp install claude-code
command. This automatically handles the configuration, dependency management, and calls Claude Code’s built-in MCP management system.
file.py:object
notation as the run
command. If no object is specified, it will automatically look for a FastMCP server object named mcp
, server
, or app
in your file:
claude mcp add
command.
Dependencies
FastMCP provides flexible dependency management options for your Claude Code servers: Individual packages: Use the--with
flag to specify packages your server needs. You can use this flag multiple times:
requirements.txt
file with all your dependencies, use --with-requirements
to install them:
--with-editable
to install them in editable mode:
fastmcp.json
configuration file (recommended):
fastmcp.json
Python Version and Project Configuration
Control the Python environment for your server with these options: Python version: Use--python
to specify which Python version your server requires. This ensures compatibility when your server needs specific Python features:
--project
to run your server within a specific project context. This tells uv
to use the project’s configuration files and virtual environment:
Environment Variables
If your server needs environment variables (like API keys), you must include them:.env
file:
Claude Code must be installed. The integration looks for the Claude Code CLI at the default installation location (
~/.claude/local/claude
) and uses the claude mcp add
command to register servers.Manual Configuration
For more control over the configuration, you can manually use Claude Code’s built-in MCP management commands. This gives you direct control over how your server is launched:Using the Server
Once your server is installed, you can start using your FastMCP server with Claude Code. Try asking Claude something like:“Roll some dice for me”Claude will automatically detect your
roll_dice
tool and use it to fulfill your request, returning something like:
I’ll roll some dice for you! Here are your results: [4, 2, 6] You rolled three dice and got a 4, a 2, and a 6!Claude Code can now access all the tools, resources, and prompts you’ve defined in your FastMCP server. If your server provides resources, you can reference them with
@
mentions using the format @server:protocol://resource/path
. If your server provides prompts, you can use them as slash commands with /mcp__servername__promptname
.