nodered-mcp

Minimal MCP server (Streamable HTTP) wrapping the Node-RED admin API. No third-party Node-RED client libraries — plain fetch calls only.

Tools

• list_flows — GET /flows, returns tab id/label list
• get_flow — GET /flow/:id
• deploy_flow — PUT /flow/:id (single-tab replace, never touches other tabs). Reads the existing tab first and logs existing vs. incoming node count so an accidental overwrite is obvious.
• create_flow — POST /flow (single new tab, not the whole flowset)
• get_nodes — GET /nodes
• get_context — GET /context/global (requires Context API enabled on the target instance)
• install_modules — POST /nodes {module}. Runs npm install inside the Node-RED runtime. This is equivalent to shell access on that host — there is no allowlist. Do not expose this server to anything you wouldn't hand a shell to.

Config

The container reads its config from a host-mounted .env file at /app/.env (loaded via dotenv/config), not from compose environment: entries or Portainer stack variables — see docker-compose.yml's volume mount. On the deployment host, create the secrets directory and file yourself (mode 700 / 600, root-owned) rather than entering values through Portainer's UI:

/opt/nodered-mcp/secrets/.env

using the format in .env.example:

• NODE_RED_URL — base URL of the Node-RED instance
• NODE_RED_USERNAME / NODE_RED_PASSWORD — HTTP Basic credentials for the auth proxy in front of Node-RED (sent as Authorization: Basic ...)
• MCP_API_KEY — random key required as an x-api-key header on every request to /mcp. This server has no Node-RED-side auth of its own beyond what Node-RED enforces, so MCP_API_KEY is the only thing gating access to it directly — generate a long random value and don't reuse it elsewhere.

Run

docker compose up -d --build