n8n and MCP: connect one agent tool and inspect its result

Understand what the connected tool is for

The March 2025 video introduces MCP and an n8n agent workflow. Its short description asks what MCPs are; the detailed chapter list supplies the route through community nodes, tool configuration and Gmail. This companion follows those documented stages without inventing the missing node JSON or installation commands.

The setup section begins at 3:09 and community-node installation at 4:29. Before adding a tool, choose one job it enables. A model composing an answer and a tool reading or changing an external record are different actions to inspect.

1. Identify the task and the external information it needs.
2. Follow the recorded community-node installation.
3. Check that the intended tool is available to the agent.

Trace the request through the workflow

Agent construction starts at 7:34 and MCP tool configuration at 10:48. Keep the tool inputs and returned fields clear. An agent can produce a plausible response even when it used the wrong source or did not invoke the tool needed for the job.

Start with a small request and inspect the actual n8n execution. Compare the question, tool call and returned material rather than accepting the final sentence as evidence that the connection works. Keep errors visible at the stage where they occur.

1. Run a request whose result you can check.
2. Inspect the tool input and response within the execution.
3. Compare the agent’s answer with that actual response.

Check Gmail authentication separately

Gmail integration begins at 13:42, Google Cloud authentication at 18:50 and final testing at 26:47. This is authentication supporting an AI workflow, not a general cloud-certification lesson. Keep the intended mailbox and the tool’s access clear while following the historical setup.

For a mail task, inspect which record the tool reads and what action the agent proposes. A connected account does not by itself approve sending a new message. The description provides no complete credentials recipe or successful outcome for every possible tool; use the recorded test and your own small result to assess the connection before expanding the task.

The takeaway

Verify the tool path and the actual account result; MCP setup and a completed agent task are separate checks.