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 🔧

1. Anthropic API Key (for Claude):

export ANTHROPIC_API_KEY='your-api-key'

2. 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

1. Using Claude 3.5 Sonnet:

mcphost

2. 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