LABSCO SUMMARY

The client stays connected while the server restarts, and requests are buffered in the gap.

That is the difference from restarting by hand: no reconnecting the client, no lost messages, no re-running the conversation to get back where you were. One thing to expect — code changes apply on their own, but a schema change still needs the server toggled off and on in Claude Desktop's settings.

What it is

A hot-reload monitor for MCP servers — nodemon's idea applied to the Model Context Protocol. It runs as a transparent proxy between your client and your server and restarts the server on file changes.

What you get

Wrap any MCP server command with mcpmon — Node, Python, Deno, anything
Your client stays connected across restarts; requests are buffered so nothing is lost
Mcpmon setup rewrites an existing server config for hot reload, with --all, --list and --restore
Your original config backed up first, and the command is safe to run more than once
Zero configuration by default; MCPMON_WATCH adds files, MCPMON_DELAY changes the restart delay, MCPMON_VERBOSE shows what it sees
Importable as a library if you want to build your own monitoring

Requirements

Node.js 16 or higher. npm install -g mcpmon, or run it without installing via npx mcpmon node server.js. Version 0.3.0.

Setup effort

One command — npm install -g mcpmon

See installation options

USE CASES

01

Iterating on a server you are writing

Save the file and call the tool again; the running server is already the new one.

02

Turning hot reload on for a server you already configured

Run the setup command against its name and let it rewrite the config.

03

Debugging through the MCP Inspector

Launch the Inspector with mcpmon in front of your server command.

04

Getting your original config back

Restore from the backup it made before touching anything.

BEFORE YOU INSTALL

What to know first

Requires

mcpmon on PATH

INSTALLATION

Connect your client

Server setup

TERMINAL

npm install -g mcpmon

MCP Clients

Claude Code

CLAUDE CODE · JSON

{
  "mcpServers": {
    "my-server": {
      "command": "mcpmon",
      "args": [
        "node",
        "server.js"
      ],
      "env": {
        "API_KEY": "<YOUR_API_KEY>"
      }
    }
  }
}

Claude Desktop

CLAUDE DESKTOP · JSON

{
  "mcpServers": {
    "my-server": {
      "command": "/Users/<YOUR_USERNAME>/.nvm/versions/node/v22.15.0/bin/node",
      "args": [
        "/usr/local/bin/mcpmon",
        "python",
        "server.py"
      ],
      "env": {
        "PYTHONPATH": "<YOUR_PATH_TO_MODULES>"
      }
    }
  }
}

MCP Inspector

MCP INSPECTOR · TERMINAL

npx @modelcontextprotocol/inspector mcpmon node server.js

mcpmon