n8n_stop_execution · Mcp N8n MCP: Risk & Policy

WHAT IT DOES

What n8n_stop_execution does on Mcp N8n

AI agents invoke n8n_stop_execution to trigger actions in Mcp N8n. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why n8n_stop_execution needs a policy

Stopping a running execution is an action that triggers real-time control over external operations managed by n8n. While not destructive (the execution record remains), it interrupts active processes and could disrupt business workflows. This falls under Execute rather than Write because it controls/terminates an active operation rather than creating or modifying data reversibly.

From the tool's definition Tool name 'n8n_stop_execution' and description 'Stop a running execution' indicate this triggers an external operation (halting a workflow execution) whose effects depend on which execution is targeted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

n8n_stop_execution Rate-limited

n8n_stop_execution stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "n8n_stop_execution": {
      "limits": [
        {
          "counter": "n8n_stop_execution_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Mcp N8n, so you can run agents against it safely.

FAQ

Questions about n8n_stop_execution

What does the n8n_stop_execution tool do? +

Stop a running execution. It is categorised as a Execute tool in the Mcp N8n MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on n8n_stop_execution? +

Register the Mcp N8n MCP server in PolicyLayer and add a rule for n8n_stop_execution: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Mcp N8n. Nothing to install.

What risk level is n8n_stop_execution? +

n8n_stop_execution is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit n8n_stop_execution? +

Yes. Add a rate_limit block to the n8n_stop_execution rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block n8n_stop_execution completely? +

Set action: deny in the PolicyLayer policy for n8n_stop_execution. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides n8n_stop_execution? +

n8n_stop_execution is provided by the Mcp N8n MCP server (lyzetam/mcp-n8n). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.