Why I Made This (Now)

Yes, I know that the official MCP roadmap includes remote MCP support in the first quarter of 2025. However, the need for remote access was immediate for me, and likely for many others. This library was created to bridge that gap, providing a way to connect to a remote MCP server from a local MCP client right now, without waiting for future official implementations.

Note: I don't want this to be a sophisticated or overcomplicated thing. This way just works right now.

Getting Started

Note: This project is currently under active development and is considered experimental. Expect breaking changes and potential issues.

Client Usage

Use Publicly Published Package

Just put the following code in your MCP client settings, in here I'm using Claude as an example:

{
  "mcpServers": {
    "remote-mcp": {
      "command": "npx",
      "args": ["-y", "@remote-mcp/client"],
      "env": {
        "REMOTE_MCP_URL": "http://localhost:9512",
        "HTTP_HEADER_Authorization": "Bearer <token>"
      }
    }
  }
}

Code Your Own Local MCP Server

Install requirements:

$ npm install @remote-mcp/client @trpc/client@next zod

then write your own code like the following:

import { RemoteMCPClient } from "@remote-mcp/client";

const client = new RemoteMCPClient({
  remoteUrl: "http://localhost:9512",

  onError: (method, error) => console.error(`Error in ${method}:`, error)
});

void client.start();

Server Usage (Remote MCP Implementation)

You can see some examples in the examples directory.

• Cloudflare Workers
• Standalone Node.js

Code Your Own Remote MCP Server

After npm install @remote-mcp/server, you can your own remote MCP server like the following:

import { MCPRouter, LogLevel } from "@remote-mcp/server";
import { createHTTPServer } from '@trpc/server/adapters/standalone';

import { z } from "zod";

// Create router instance
const mcpRouter = new MCPRouter({
  logLevel: LogLevel.DEBUG,
  name: "example-server",
  version: "1.0.0",
  capabilities: {
    logging: {},
  },
});

// Add example tool
mcpRouter.addTool(
  "calculator",
  {
    description:
      "Perform basic calculations. Add, subtract, multiply, divide. Invoke this every time you need to perform a calculation.",
    schema: z.object({
      operation: z.enum(["add", "subtract", "multiply", "divide"]),
      a: z.string(),
      b: z.string(),
    }),
  },
  async (args) => {
    const a = Number(args.a);
    const b = Number(args.b);

    let result: number;
    switch (args.operation) {
      case "add":
        result = Number(a) + b;
        break;
      case "subtract":
        result = a - b;
        break;
      case "multiply":
        result = a * b;
        break;
      case "divide":
        if (b === 0) throw new Error("Division by zero");
        result = a / b;
        break;
    }

    return {
      content: [{ type: "text", text: `${result}` }],
    };
  },
);

const appRouter = mcpRouter.createTRPCRouter();

void createHTTPServer({
  router: appRouter,
  createContext: () => ({}),
}).listen(Number(process.env.PORT || 9512));

Then you can see like the following in your MCP client:

Packages

This repository contains:

• @remote-mcp/client: Client library acting as a local MCP server, connecting to a remote implementation.
• @remote-mcp/server: Server library for creating remotely accessible MCP services (used as the remote implementation).

Roadmap

Core Features

• [x] Basic Type-safe Client/Server Communication
  • [x] Basic MCP Command Support
  • [x] Basic MCP Tool Support
  • [x] Basic MCP Prompt Support
  • [ ] Crash-Safe Handling (WIP, top priority)
• [ ] Complete Event Subscription System
  • [ ] Resource change notifications
  • [ ] Tool/Prompt list change notifications
• [ ] HTTP Header Support
  • [x] Custom Headers
  • [ ] Authentication Middleware
• [ ] Basic error handling improvements
• [ ] Basic middleware support

Framework Support

• [ ] Nest.js Integration (@remote-mcp/nestjs)

Advanced Features

• [ ] Bidirectional communication
  • [ ] Server-to-client requests
  • [ ] Resource sharing between server/client
• [ ] Basic monitoring & logging

Contribute

Contributions are welcome. See CONTRIBUTING.md for details.

Disclaimer

This library is a complementary extension, not part of the official MCP specification, built upon existing MCP concepts.

License

This project is licensed under the MIT License. See the LICENSE file for details.

References

• Model Context Protocol