Nest MCP Sse

🚀 Nest-mcp-sse

Nest-mcp-sse is a dynamic module designed for rapid development of SSE (Server-Sent Events) - type McpServer in NestJS projects. It simplifies interactions with McpServer, allowing developers to focus on core MCP tool development without dealing with connection transport, lifecycle management, and message passing.

🚀 Quick Start

Nest-mcp-sse is a dynamic module that streamlines the process of developing an SSE - type McpServer in NestJS projects. It takes care of the underlying details, enabling developers to concentrate on the core functionality of MCP tools.

✨ Features

• Rapid MCP Server Creation: Quickly start an MCP server with simple configuration.
• Multiple Instance Management: Support for managing and running multiple McpServer instances simultaneously.
• Automatic SSE Connection Lifecycle Handling: The module has built - in automatic management for SSE connections, simplifying connection establishment and maintenance.

📦 Installation

npm install nest-mcp-sse
# or
yarn add nest-mcp-sse
# or
pnpm add nest-mcp-sse

💻 Usage Examples

Basic Usage

1. Import the Module

Import the McpModule in your NestJS module:

import { Module } from '@nestjs/common';
import { McpModule } from 'nest-mcp-sse';

@Module({
  imports: [McpModule.register({
    controllerBaseUrl: 'api/mcp',
    mcpServerConfigs: [
      {
        serverId: 'default-server', // Unique identifier for the MCP Server
        serverInfo: {
          name: 'Default Server', // First parameter passed directly to the McpServer class of MCP TS - SDK
          options: { /* Second parameter passed directly to the McpServer class of MCP TS - SDK */ }
        }
      }
    ]
  })],
})
export class AppModule {}

2. Operate McpServer Instances

You can manage multiple McpServer instances through the McpServerService:

import { McpServerService } from 'nest-mcp-sse';

@Injectable()
export class MyService {
  constructor(
    private readonly mcpServerService: McpServerService,
  ) {}

  // Register a new MCP Server instance
  async registerMcpServer() {
    const server = await this.mcpServerService.registerServer({
      serverId: 'new-server',
      serverInfo: { /* Configuration parameters */ },
    });
    return server;
  }

  // Get an MCP Server instance with a specified ID
  getMcpServer(serverId: string) {
    return this.mcpServerService.getServer(serverId);
  }

  // Check if an MCP Server instance is registered
  hasMcpServer(serverId: string) {
    return this.mcpServerService.hasServer(serverId);
  }
}

3. Manually Register Server Instances

If you want to manually manage McpServer connections, you can use the following method:

import { McpServerService } from 'nest-mcp-sse';

// Register a new MCP Server instance
const server = await mcpServerService.registerServer({
  serverId: 'manual-server',
  serverInfo: { /* Configuration parameters */ },
});

// Connect the MCP Server to the transport layer
await mcpServerService.connect('manual-server', transportInstance);

Advanced Usage

Automatic Server Endpoints Creation

The module automatically creates the following two endpoints for each McpServer instance:

• SSE Connection Endpoint: {controllerBaseUrl}/{serverId}/connect
  • Example URL: http://localhost:3000/api/mcp/default-server/connect
• Message Handling Endpoint: {controllerBaseUrl}/{serverId}/messages
  • Example URL: http://localhost:3000/api/mcp/default-server/messages

Custom Endpoint Names

You can customize the names of SSE and message endpoints when registering the module:

McpModule.register({
  controllerBaseUrl: 'api/mcp',
  sseEndpoint: 'custom-sse', // Default is 'sse'
  messagesEndpoint: 'custom-messages', // Default is 'messages'
  mcpServerConfigs: [
    {
      serverId: 'default-server',
      serverInfo: { /* Configuration parameters */ },
    }
  ],
});

Other Configuration Options

• Transport Layer Management: The module supports custom transport layer implementations, allowing developers to extend functionality as needed.
• Message Handling: The message - handling capabilities of McpServer can be extended through a plugin mechanism.

📚 Documentation

A complete usage example can be found in the official documentation or the example project of the module.

🤝 Contribution and Support

• If you find any issues or have improvement suggestions, please submit an Issue.
• Contributions via Pull Requests are welcome!