Click on "Install Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@MCP Express Serveradd 15 and 27"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
MCP Express Server
A Model Context Protocol (MCP) server implementation using TypeScript, Express.js, and Server-Sent Events (SSE) for real-time communication.
Features
MCP Protocol Support: Implements the Model Context Protocol specification
SSE Transport: Real-time communication using Server-Sent Events
TypeScript: Fully typed for better developer experience
Express.js: Robust HTTP server framework
Environment Configuration: Using dotenv for configuration management
Project Structure
src/
├── index.ts # Main entry point and Express server setup
├── server.ts # MCP protocol handling and SSE transport layer
├── tools.ts # Tool implementations and business logic
└── types.ts # TypeScript type definitionsInstallation
npm installConfiguration
Create a .env file in the root directory:
cp .env.example .envEdit .env with your configuration:
PORT=3000
HOST=0.0.0.0
SERVER_NAME=mcp-express-server
SERVER_VERSION=1.0.0Development
Run in development mode with auto-reload:
npm run devBuild
Compile TypeScript to JavaScript:
npm run buildProduction
Run the compiled server:
npm startAPI Endpoints
GET /
Server information and available endpoints
GET /health
Health check endpoint
Returns server status and active connection count
GET /sse
Server-Sent Events endpoint
Establishes a persistent connection for real-time notifications
Clients should connect here to receive server updates
POST /message
MCP message endpoint
Send JSON-RPC 2.0 formatted MCP requests
Receives MCP responses
Available Tools
The server comes with three example tools:
echo: Echoes back a message
add: Adds two numbers together
get_time: Returns the current server time
MCP Protocol Usage
Initialize Connection
curl -X POST http://localhost:3000/message \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"id": 1,
"method": "initialize",
"params": {
"protocolVersion": "2024-11-05",
"capabilities": {},
"clientInfo": {
"name": "test-client",
"version": "1.0.0"
}
}
}'List Available Tools
curl -X POST http://localhost:3000/message \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"id": 2,
"method": "tools/list"
}'Call a Tool
curl -X POST http://localhost:3000/message \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"id": 3,
"method": "tools/call",
"params": {
"name": "add",
"arguments": {
"a": 5,
"b": 3
}
}
}'Adding New Tools
Edit src/tools.ts to add new tools:
export const availableTools: Tool[] = [
// ... existing tools
{
name: 'your_tool',
description: 'Description of your tool',
inputSchema: {
type: 'object',
properties: {
param1: {
type: 'string',
description: 'Parameter description'
}
},
required: ['param1']
}
}
];
// Add implementation in executeTool function
case 'your_tool':
return {
content: [{
type: 'text',
text: `Result: ${args.param1}`
}]
};License
MIT
