🤖 Copilot Chat MCP Extension

A VS Code extension that integrates with GitHub Copilot Chat to provide multiplication functionality using the MCP server.

🎯 What This Does

This extension allows you to:

1. Type in Copilot Chat: @mcp-calculator multiply 6 and 7
2. Get instant results: 6 × 7 = 42
3. All within Copilot Chat interface - no separate windows or popups
4. Uses MCP server at https://at-mcp-demo.dev.commandcentral.com/

🚀 Quick Start

Prerequisites

1. VS Code with GitHub Copilot installed and active
2. MCP Server available at https://at-mcp-demo.dev.commandcentral.com/

Setup

1. Install dependencies:

   npm install
   

2. Compile the extension:

   npm run compile
   

3. Start the MCP server:

   cd ../mcp-server-demo
   npm start
   

4. Test in VS Code:

   • Press F5 to launch Extension Development Host
   • Open Copilot Chat (Ctrl+Alt+I)
   • Type: @mcp-calculator multiply 6 and 7
   • See result: 6 × 7 = 42

💬 How to Use in Copilot Chat

Basic Usage

@mcp-calculator multiply 6 and 7
@mcp-calculator multiply 2.5 by 4
@mcp-calculator multiply 10 * 3

Get Help

@mcp-calculator help

Example Conversation

You: @mcp-calculator multiply 6 and 7
Bot: 🧮 Multiplication Result
     6 × 7 = 42
     ✅ Calculated using MCP server

You: @mcp-calculator multiply 2.5 by 4  
Bot: 🧮 Multiplication Result
     2.5 × 4 = 10
     ✅ Calculated using MCP server

🛠️ Features

• Natural language input: "multiply 6 and 7", "multiply 2.5 by 4"
• Multiple formats: "and", "by", "*" all work
• Error handling: Graceful handling when server is down
• Help system: Built-in help and examples
• Follow-up suggestions: Copilot suggests next actions
• Real-time validation: Checks if MCP server is available

Technical Details

Chat Participant

• ID: mcp.calculator
• Name: @mcp-calculator
• Description: MCP Calculator for mathematical operations

Supported Commands

• multiply: Multiply two numbers
• help: Show usage instructions

Input Patterns

The extension recognizes these patterns:

• multiply X and Y
• multiply X by Y
• multiply X * Y
• Where X and Y are numbers (including decimals)

Testing

Manual Testing

1. Start MCP Server: cd mcp-server-demo && npm start
2. Launch Extension: Press F5 in VS Code
3. Open Copilot Chat: Ctrl+Alt+I
4. Test Commands:

   @mcp-calculator multiply 6 and 7
   @mcp-calculator multiply 2.5 by 4
   @mcp-calculator help
   

Expected Results

• ✅ Multiplication: Shows result with calculation
• ✅ Error handling: Shows helpful message if server down
• ✅ Help: Shows usage instructions
• ✅ Follow-ups: Suggests related actions

🛡️ Error Handling

Server Not Running

❌ MCP Server not available

Please start the MCP server first:
cd mcp-server-demo
npm start

Invalid Input

❓ I can help you multiply numbers!

Try: multiply 6 and 7 or multiply 2.5 by 4
Type help for more information.

Network Errors

❌ Error calling MCP server
[Detailed error message]

📁 Project Structure

copilot-chat-extension/
├── src/
│   └── extension.ts          # Main extension logic
├── out/                      # Compiled JavaScript
├── .vscode/
│   ├── launch.json           # F5 debug config
│   └── tasks.json            # Build tasks
├── package.json              # Extension manifest
├── tsconfig.json             # TypeScript config
└── README.md                 # This file

🔄 Integration with MCP Server

The extension communicates with the MCP server at:

• Manifest: GET https://at-mcp-demo.dev.commandcentral.com/.well-known/mcp/manifest.json
• Multiply: POST https://at-mcp-demo.dev.commandcentral.com/tools/MultiplyNumbers/invoke

Request Format:

{
  "a": 6,
  "b": 7
}

Response Format:

{
  "result": 42
}

Troubleshooting

Copilot Chat Not Available

• Ensure GitHub Copilot is installed and activated
• Check VS Code version (requires 1.90.0+)
• Restart VS Code if needed

Extension Not Loading

• Check VS Code Extension Host output
• Verify compilation: npm run compile
• Restart Extension Development Host

MCP Server Issues

• Verify server is accessible: Test at https://at-mcp-demo.dev.commandcentral.com/
• Check server logs for errors
• Test server directly: Invoke-RestMethod -Uri "https://at-mcp-demo.dev.commandcentral.com/.well-known/mcp/manifest.json"

** Now you can use MCP tools directly in GitHub Copilot Chat!**