MCPHost 🤖

A CLI host application that enables Large Language Models (LLMs) to interact with external tools through the Model Context Protocol (MCP). Currently supports both Claude 3.5 Sonnet and Ollama models.

Overview 🌟

MCPHost acts as a host in the MCP client-server architecture, where:

Hosts (like MCPHost) are LLM applications that manage connections and interactions
Clients maintain 1:1 connections with MCP servers
Servers provide context, tools, and capabilities to the LLMs

This architecture allows language models to:

Access external tools and data sources 🛠️
Maintain consistent context across interactions 🔄
Execute commands and retrieve information safely 🔒

Currently supports:

Claude 3.5 Sonnet (claude-3-5-sonnet-20240620)
Any Ollama-compatible model with function calling support

Features ✨

Interactive conversations with either Claude 3.5 Sonnet or Ollama models
Support for multiple concurrent MCP servers
Dynamic tool discovery and integration
Tool calling capabilities for both model types
Configurable MCP server locations and arguments
Consistent command interface across model types
Configurable message history window for context management

Requirements 📋

Go 1.23.3 or later
For Claude: An Anthropic API key
For Ollama: Local Ollama installation with desired models
One or more MCP-compatible tool servers

Environment Setup 🔧

Anthropic API Key (for Claude):

export ANTHROPIC_API_KEY='your-api-key'

Ollama Setup:

Install Ollama from https://ollama.ai
Pull your desired model:

ollama pull mistral

Ensure Ollama is running:

ollama serve

Installation 📦

go install github.com/mark3labs/mcphost@latest

Configuration ⚙️

MCPHost will automatically create a configuration file at ~/.mcp.json if it doesn't exist. You can also specify a custom location using the --config flag:

{
  "mcpServers": {
    "sqlite": {
      "command": "uvx",
      "args": [
        "mcp-server-sqlite",
        "--db-path",
        "/tmp/foo.db"
      ]
    },
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "/tmp"
      ]
    }
  }
}

Each MCP server entry requires:

command: The command to run (e.g., uvx, npx)
args: Array of arguments for the command:
- For SQLite server: mcp-server-sqlite with database path
- For filesystem server: @modelcontextprotocol/server-filesystem with directory path

Usage 🚀

Basic Commands

Using Claude 3.5 Sonnet:

mcphost

Using Ollama:

mcphost ollama --model mistral

Note: Tool support in Ollama requires models that support function calling.

Additional Options

Custom config file:

mcphost --config /path/to/config.json

Set message history window:

mcphost --message-window 15

Interactive Commands

While chatting, you can use:

/help: Show available commands
/tools: List all available tools
/servers: List configured MCP servers
/history: Display conversation history
/quit: Exit the application
Ctrl+C: Exit at any time

Global Flags

--config: Specify custom config file location
--message-window: Set number of messages to keep in context (default: 10)

MCP Server Compatibility 🔌

MCPHost can work with any MCP-compliant server. For examples and reference implementations, see the MCP Servers Repository.

Contributing 🤝

Contributions are welcome! Feel free to:

Submit bug reports or feature requests through issues
Create pull requests for improvements
Share your custom MCP servers
Improve documentation

Please ensure your contributions follow good coding practices and include appropriate tests.

License 📄

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments 🙏

Thanks to the Anthropic team for Claude and the MCP specification
Thanks to the Ollama team for their local LLM runtime
Thanks to all contributors who have helped improve this tool