Enable n8n's Built-In MCP Server and Build a Workflow From a Plain-English Prompt

n8n ships a node that flips the usual direction of automation: instead of n8n calling out to an AI model, an AI assistant calls into n8n. The MCP Server Trigger node turns a workflow into a tool that any Model Context Protocol client — Claude Desktop, Claude Code, or anything else that speaks MCP — can discover and run. Ask the assistant in plain English, and it invokes your workflow directly.

Before you start

You'll need a running n8n instance (Cloud, self-hosted Community Edition, or Enterprise all support the MCP Server Trigger node — a free n8n Cloud trial is the fastest way to get one if you don't have an instance yet) and an MCP client to test with — this walkthrough uses Claude Desktop. No community nodes or extra installs are required on the n8n side; the node ships in n8n's built-in LangChain node package.

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Step 1: Add the MCP Server Trigger node

Create a new workflow and add the MCP Server Trigger node as its starting point. Unlike a normal trigger, this node doesn't fire on a schedule or a webhook — it stays listening, and its only job is to expose whatever tool nodes you connect to it.

Open the node's panel and note the Path field: by default it's a randomly generated segment of the MCP URL, which is fine for a first test. You can set a fixed path later if you want a stable URL to hand out.

Step 2: Expose a workflow as a tool

The trigger does nothing on its own — it needs at least one tool node connected to it. Add a Custom n8n Workflow Tool node and point it at the workflow you want the assistant to run (this can be the same workflow, or a separate one you've already built, like the folder-watcher from an earlier post).

Give the tool a clear Name and Description. The description is what the AI actually reads to decide when to call it — write it the way you'd explain the tool to a new teammate: what it does, and when to use it. A vague description gets skipped or misused; a specific one ("Archives a file at the given path into the archive folder") gets called at the right moment.

Step 3: Secure it with Bearer auth

An MCP endpoint with no authentication is an open door into your automations — anyone with the URL can call your tools. In the MCP Server Trigger node, set Authentication to Bearer Auth, then create a new credential and generate a token. Keep the token in the credential, not pasted into the workflow body.

Save and activate the workflow. With the workflow active, reopen the trigger node panel — it now shows the live MCP URL and the Bearer Token you'll need for the next step.

Step 4: Connect an MCP client

Claude Desktop (like most current MCP clients) expects a local process it can talk to over stdio, not a raw HTTPS URL, so you bridge the two with mcp-remote, a small proxy built for exactly this. Add an entry to your claude_desktop_config.json:

{
  "mcpServers": {
    "n8n": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://your-n8n-instance.example.com/mcp/<your-path>/sse",
        "--header",
        "Authorization: Bearer ${N8N_MCP_TOKEN}"
      ]
    }
  }
}

Replace the URL with the MCP URL from Step 3, and set N8N_MCP_TOKEN in your environment to the Bearer token. Save the file and restart Claude Desktop — it reads this config on launch.

Step 5: Trigger it with a plain-English prompt

Open a new chat in Claude Desktop and ask for the thing your tool does, in ordinary language — no slash commands, no JSON. If your tool description was specific, Claude recognizes it needs your n8n tool, calls it with the right input, and reports back what happened. Check the n8n execution log for the run to confirm it actually fired and see exactly what input the assistant sent.

Tip: If Claude doesn't call the tool when you expect it to, the description is almost always the fix — not the prompt. Make it more concrete about what the tool does and what kind of request it applies to.

What's next

One workflow behind one tool is the starting point. The same MCP Server Trigger accepts multiple Custom n8n Workflow Tool nodes, so a single MCP connection can expose your whole library of automations to an assistant at once — letting you describe a multi-step task in plain English and have it call several of your workflows in sequence.