npm_create_user · Nginx Manager MCP: Risk & Policy

WHAT IT DOES

What npm_create_user does on Nginx Manager

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

WHY IT NEEDS A POLICY

Why npm_create_user needs a policy

Creating a user is a Write operation—it adds data (a new user account) to the system in a reversible manner (the user can be deleted later). This is not a Read operation (no data retrieval), not Execute (no arbitrary code execution), not Destructive (creation is reversible), and not Financial (no money involved).

From the tool's definition Tool name is 'npm_create_user' and description states 'Create a new user.' This is a creation operation that modifies system state by adding a new user account to the Nginx Proxy Manager system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

npm_create_user Rate-limited

npm_create_user 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": {
    "npm_create_user": {
      "limits": [
        {
          "counter": "npm_create_user_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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

FAQ

Questions about npm_create_user

What does the npm_create_user tool do? +

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

How do I enforce a policy on npm_create_user? +

Register the Nginx Manager MCP server in PolicyLayer and add a rule for npm_create_user: 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 Nginx Manager. Nothing to install.

What risk level is npm_create_user? +

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

Can I rate-limit npm_create_user? +

Yes. Add a rate_limit block to the npm_create_user 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 npm_create_user completely? +

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

npm_create_user is provided by the Nginx Manager MCP server (kognar-ai/ngnix-manager-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.