MCP Host CLI

What is MCP Host CLI?

It is a FastAPI server for chat interactions with LLMs, using OpenAI-compatible providers. It is configured via environment variables and CLI arguments, and supports tool approval workflows.

How to use MCP Host CLI?

Configure via environment variables (e.g., LLM_API_KEY, LLM_MODEL) or CLI arguments (e.g., --model, --port). Start the server using uv run main.py with desired options. Send requests to endpoints like POST /user_request and POST /approve.

Key features of MCP Host CLI

• FastAPI server for chat interactions with LLMs
• Configurable via environment variables and CLI arguments
• Supports OpenAI-compatible providers (e.g., OpenRouter)
• Tool approval workflow with request/response endpoints
• Streaming mode and retry on LLM errors

Use cases of MCP Host CLI

• Building a backend for chat interfaces with LLMs
• Integrating LLM chat with tool approval mechanisms
• Running a local or remote LLM chat server with OpenAI-compatible API

FAQ from MCP Host CLI

How do I configure the LLM model?

Use the LLM_MODEL environment variable or the --model CLI argument. Default is qwen2.5-coder:latest.

How do I provide the API key?

Set the LLM_API_KEY environment variable or use the --api-key-file CLI argument pointing to a file with the key.

What LLM providers are supported?

Only openai provider is supported, but the base URL can be changed (default OpenRouter).

How do I approve a tool call?

Send a POST request to /approve with request_id and approve boolean in the JSON body.

Where are debug messages logged?

If --debug-messages is enabled, logs are written to /tmp/llm-requester.messages.log.