LABSCO SUMMARY

One environment variable decides what you are connected to.

Because the whole configuration is a key, swapping which hosted server your client talks to is a one-line change rather than a new install — and nothing runs on your machine except the relay. The corollary is that the hosted side owns availability and whatever credentials that server needs, so this is a convenience layer rather than an isolation layer.

What it is

A proxy. It runs locally over stdio and forwards to a server hosted on MCP.so, so a client that only speaks stdio can use a remote server without you deploying anything.

What you get

Whatever the hosted server exposes appears in your client — the proxy relays the tool list and the calls; you choose which server by the key you configure

Requirements

The npm package mcprouter, version 0.1.7, run through npx with SERVER_KEY set. The key comes from mcp.so: pick a hosting server there and click Connect to generate one that is yours.

Setup effort

One command plus a key — npx -y mcprouter, then supply credentials

See installation options

USE CASES

01

Using a server you do not want to host

Point the client at the hosted instance with a key instead of installing and running it locally.

02

Trying several servers quickly

Swap the key to move between hosted servers without touching the rest of the config.

BEFORE YOU INSTALL

What to know first

Requires

npx on PATH
SERVER_KEY in your environment

Where it runs

The documented client runs the server on your machine.

INSTALLATION

Connect your client

Server setup

TERMINAL

npx -y mcprouter

MCP Clients

Claude Desktop

CLAUDE DESKTOP · JSON

{
  "mcpServers": {
    "fetch": {
      "command": "npx",
      "args": [
        "-y",
        "mcprouter"
      ],
      "env": {
        "SERVER_KEY": "<YOUR_SERVER_KEY>"
      }
    }
  }
}

mcprouter