Error integrating MCP tool

Questions
1

What’s the issue?**

Describe the problem/error/question

have an MCP tool server and I am trying to integrate it with an AI agent. It is accessible through HTTP Streaming. I know it works because Claude Desktop is able to use it. Connecting it to the agent works, the n8n UI shows the different tools available with the server. However, when the workflow runs, I get the error.

What is the error message (if any)?

ToolExecutor can not be found

Please share your workflow

(Select the nodes on your canvas and use the keyboard shortcuts CMD+C/CTRL+C and CMD+V/CTRL+V to copy and paste the workflow.)

{
“nodes”: [
{
“parameters”: {
“options”: {
“systemMessage”: “You are a helpful assistant. Use the weather tool to get the weather for the city mentioned.”
}
},
“type”: “@n8n/n8n-nodes-langchain.agent”,
“typeVersion”: 2.2,
“position”: [
208,
0
],
“id”: “ed8eedc3-c180-4eb8-9443-6395c8500f69”,
“name”: “AI Agent”
}
],
“connections”: {},
“pinData”: {},
“meta”: {
“templateCredsSetupCompleted”: true,
“instanceId”: “5ff714de7143ef8ac36a79d482e40d49a0d35b405548a00c0c1748432a94125f”
}
}

Share the output returned by the last node

Information on your n8n setup

  • n8n version: 1.116.2
  • Database (default: SQLite):
  • n8n EXECUTIONS_PROCESS setting (default: own, main):
  • Running n8n via (Docker, npm, n8n cloud, desktop app):
  • Operating system:
2

yeah, the “ToolExecutor can not be found” error happens when the agent node can’t locate the tool you’re trying to use. this is usually a mismatch between how the tool is defined and how the agent is trying to access it.

few things to check:

**1. make sure your MCP server tool is properly connected to the agent**

- in your agent node, did you add the MCP tool using the “Add Tool” button?

- the tool should show up in the agent’s tool list with the exact name your MCP server exposes

**2. verify the tool name matches exactly**

this one trips people up - if your MCP server exposes a tool called `get_weather` but the agent is looking for `getWeather` (or vice versa), it’ll fail. check your MCP server’s tool definitions and make sure the agent is using the exact same name.

**3. check if its a version/compatibility issue**

- what version of n8n are you running? MCP support got better in recent versions

- if youre on an older version, you might need to update

**4. try this in your agent node:**

- go to the agent config

- make sure under “Tools” you have the MCP tool added

- check that the tool definition includes the proper schema/description

since Claude Desktop works with your MCP server, the server itself is fine. the issue is definitely on the n8n side - either the tool isn’t being passed to the agent correctly, or theres a name/format mismatch.

can you share:

- what the exact tool name is from your MCP server?

- a screenshot of the “Tools” section in your agent node config?

that’ll help narrow it down

lmk what you find