nr-mcp

A Model Context Protocol (MCP) server that lets AI assistants interact with Node-RED — read flows, search nodes, edit function code, deploy changes safely, and manage modules.

Built to solve real problems: the existing Node-RED MCP implementations use PUT /flow/:id which reorders your tabs. nr-mcp uses the correct GET → POST /flows pattern with optimistic locking, so your tab order is always preserved.

Features

13 tools for complete Node-RED flow management:

Why not just use the existing MCP servers?

• Tab reorder bug: Other implementations use PUT /flow/:id which silently reorders your tabs in Node-RED. nr-mcp uses the correct GET → POST /flows full-deploy pattern.
• Optimistic locking: Every deploy checks the rev field. If someone else deployed between your read and write, you get a clear conflict error instead of silent data loss.
• Smart search: Search across node names, types, function code, templates, and actions in one call.
• Production-tested: Built and used daily for managing complex Node-RED installations (home automation, IoT, energy management).

Installation

Prerequisites

• Python 3.11+
• uv (recommended) or pip
• Node-RED instance with Admin API enabled

Install from PyPI

pip install nr-mcp

Install with uv (recommended)

uv tool install nr-mcp

Or from source:

git clone https://github.com/Texan-NXTassist/nr-mcp.git
cd nr-mcp
uv tool install .

This creates the nr-mcp command in ~/.local/bin/.

Configuration

Environment variables

* At least one auth method is recommended. Auth is checked in order: token → basic auth → no auth.

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "nr-mcp": {
      "command": "nr-mcp",
      "env": {
        "NR_URL": "http://localhost:1880",
        "NR_USER": "admin",
        "NR_PASS": "your-password"
      }
    }
  }
}

Tip: If you get a "working directory" error, create a wrapper script:

#!/bin/bash
cd /tmp
exec nr-mcp "$@"

Then point command to the wrapper path.

Cursor / VS Code

Add to your MCP settings (.cursor/mcp.json or VS Code equivalent):

{
  "mcpServers": {
    "nr-mcp": {
      "command": "nr-mcp",
      "env": {
        "NR_URL": "http://localhost:1880",
        "NR_TOKEN": "your-access-token"
      }
    }
  }
}

Usage examples

Once connected, you can ask your AI assi

... View full README on GitHub