PocketFlow MCP Demo

This project shows how to build an agent that performs addition using PocketFlow and Model Context Protocol (MCP). It presents a comparison between using MCP and basic function calling approaches.

This implementation is based on the tutorial: MCP Simply Explained: Function Calling Rebranded or Genuine Breakthrough?

Features

• Mathematical operation tools through a simple terminal interface
• Integration with Model Context Protocol (MCP)
• Comparison between MCP and direct function calling
• Simple toggle between MCP and local function calling

How to Run

1. Set your API key:

   export OPENAI_API_KEY="your-api-key-here"

   Or update it directly in utils.py

2. Install and run:

   pip install -r requirements.txt
   python main.py

MCP vs Function Calling

To compare both approaches, this demo provides local function alternatives that don't require MCP:

• Toggle with a simple flag: Set MCP = True or MCP = False at the top of utils.py to switch between MCP and local implementations.
• No code changes needed! The application automatically uses either:
  • MCP server tools when MCP = True
  • Local function implementations when MCP = False

This allows you to see the difference between the two approaches while keeping the same workflow.

Function Calling

• Functions are directly embedded in application code
• Each new tool requires modifying the application
• Tools are defined within the application itself

MCP Approach

• Tools live in separate MCP servers
• Standard protocol for all tool interactions
• New tools can be added without changing the agent
• AI can interact with tools through a consistent interface

How It Works

flowchart LR
    tools[GetToolsNode] -->|decide| decide[DecideToolNode]
    decide -->|execute| execute[ExecuteToolNode]

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The agent uses PocketFlow to create a workflow where:

1. It takes user input about numbers
2. Connects to the MCP server for mathematical operations (or uses local functions based on the MCP flag)
3. Returns the result

Files

• main.py: Implementation of the addition agent using PocketFlow
• utils.py: Helper functions for API calls and MCP integration
• simple_server.py: MCP server that provides the addition tool