MCP Docs

You can run a dedicated MCP SSE server to expose your Elixir project’s functions and dependencies to a client, enabling interactive exploration and testing of code behavior and API-like endpoints. This server is started from your project’s tooling and can be run with different entry commands to bind on the default port or a custom port.

How to use

To start the MCP SSE server that serves your Elixir project’s functions, run the start command from your development shell. The server will listen on the default port unless you specify a different one. You can experiment by launching it in an interactive session using your preferred startup flow.

How to install

Prerequisites: you need a working Elixir development environment with Mix installed. Ensure you have your project set up and dependencies installed before starting the MCP server.

Step by step commands you can run in your terminal.

# Start the MCP SSE server on the default port of 9702
mix mcp_docs.start

# Start on a specific port
mix mcp_docs.start --port 1234

# Start in an interactive session for live recompilation
iex -S mix mcp_docs.start

Configuration and usage notes

You can try the MCP server locally using the inspector utility to see how it interacts with your codebase. This helps validate that the functions and dependencies you want to expose are accessible from the client side.

Examples and practical tips

Choose the startup command that fits your workflow. If you regularly restart with a specific port, keep using the port flag to ensure clients know where to connect. For quick experiments, the default port provides a convenient baseline.

Security and best practices

Limit access to your local MCP server when working in shared environments. If you expose the server to a network, consider adding authentication or network restrictions to protect the exposed functions and data.

Troubleshooting

If the server does not start, check that your Elixir and Mix tools are correctly installed and that there are no port conflicts on the chosen port. If you make changes to your code, you can start the server in an interactive session to allow for automatic recompilation.

Notes

The server supports starting on the default port or a user-defined port. You can also run the server inside an interactive session to enable live recompilation of code during development.

MCP connection configurations

Below are example configurations that illustrate multiple ways to start the MCP server locally. These configurations ensure you can connect clients to the server and reuse the same underlying capabilities.

{
  "mcpServers": {
    "mcp_docs_default": {
      "type": "stdio",
      "name": "mcp_docs",
      "command": "mix",
      "args": ["mcp_docs.start"]
    },
    "mcp_docs_port1234": {
      "type": "stdio",
      "name": "mcp_docs",
      "command": "mix",
      "args": ["mcp_docs.start", "--port", "1234"]
    },
    "mcp_docs_iex": {
      "type": "stdio",
      "name": "mcp_docs",
      "command": "iex",
      "args": ["-S", "mix", "mcp_docs.start"]
    }
  }
}

Available tools

start_server

Launch the MCP SSE server to expose the Elixir project's functions and dependencies through an interactive client.

inspector

Run the inspector tool to experiment with your codebase via MCP integration.