MCP Simple Chatbot

This example demonstrates how to integrate the Model Context Protocol (MCP) into a simple CLI chatbot. The implementation showcases MCP's flexibility by supporting multiple tools through MCP servers and is compatible with any LLM provider that follows OpenAI API standards.

Requirements

• Python 3.10
• python-dotenv
• requests
• mcp
• uvicorn

Installation

1. Install the dependencies:

   pip install -r requirements.txt
   

2. Set up environment variables:

   Create a .env file in the root directory and add your API key:

   LLM_API_KEY=your_api_key_here
   

3. Configure servers:

   The servers_config.json follows the same structure as Claude Desktop, allowing for easy integration of multiple servers. Here's an example:

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

   Environment variables are supported as well. Pass them as you would with the Claude Desktop App.

   Example:

   {
     "mcpServers": {
       "server_name": {
         "command": "uvx",
         "args": ["mcp-server-name", "--additional-args"],
         "env": {
           "API_KEY": "your_api_key_here"
         }
       }
     }
   }
   

Usage

1. Run the client:

   python main.py
   

2. Interact with the assistant:

   The assistant will automatically detect available tools and can respond to queries based on the tools provided by the configured servers.

3. Exit the session:

   Type quit or exit to end the session.

Architecture

• Tool Discovery: Tools are automatically discovered from configured servers.
• System Prompt: Tools are dynamically included in the system prompt, allowing the LLM to understand available capabilities.
• Server Integration: Supports any MCP-compatible server, tested with various server implementations including Uvicorn and Node.js.

Class Structure

• Configuration: Manages environment variables and server configurations
• Server: Handles MCP server initialization, tool discovery, and execution
• Tool: Represents individual tools with their properties and formatting
• LLMClient: Manages communication with the LLM provider
• ChatSession: Orchestrates the interaction between user, LLM, and tools

Logic Flow

1. Tool Integration:

   • Tools are dynamically discovered from MCP servers
   • Tool descriptions are automatically included in system prompt
   • Tool execution is handled through standardized MCP protocol

2. Runtime Flow:

   • User input is received
   • Input is sent to LLM with context of available tools
   • LLM response is parsed:
     • If it's a tool call → execute tool and return result
     • If it's a direct response → return to user
   • Tool results are sent back to LLM for interpretation
   • Final response is presented to user