n8n_create_credential · Mcp N8n MCP: Risk & Policy

WHAT IT DOES

What n8n_create_credential does on Mcp N8n

AI agents use n8n_create_credential to create or update resources in Mcp N8n — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp N8n environment.

WHY IT NEEDS A POLICY

Why n8n_create_credential needs a policy

This tool creates new credentials in n8n, which are sensitive authentication artifacts used to access external systems and services. While creation itself is reversible (Write rather than Destructive), credentials are critical security-sensitive objects. Misuse could allow an AI agent to create credentials for unauthorized access to external systems, compromise integrations, or enable lateral movement.

From the tool's definition Tool name is 'n8n_create_credential' and description states 'Create a new credential.' The verb 'create' indicates data creation/modification rather than retrieval or destruction.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

n8n_create_credential Rate-limited

n8n_create_credential stays usable, but capped — an agent stuck in a loop can't make hundreds of changes 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_create_credential": {
      "limits": [
        {
          "counter": "n8n_create_credential_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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_create_credential

What does the n8n_create_credential tool do? +

Create a new credential. It is categorised as a Write tool in the Mcp N8n MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on n8n_create_credential? +

Register the Mcp N8n MCP server in PolicyLayer and add a rule for n8n_create_credential: 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_create_credential? +

n8n_create_credential is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit n8n_create_credential? +

Yes. Add a rate_limit block to the n8n_create_credential 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_create_credential completely? +

Set action: deny in the PolicyLayer policy for n8n_create_credential. 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_create_credential? +

n8n_create_credential 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.