request_certificate · Nginx Proxy Manager MCP: Risk & Policy

WHAT IT DOES

What request_certificate does on Nginx Proxy Manager MCP

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

WHY IT NEEDS A POLICY

Why request_certificate needs a policy

This tool creates new SSL certificates, which is a reversible write operation modifying the proxy infrastructure state. While not destructive (certificates can be revoked/deleted), it has high severity due to blast radius: misconfigured certificate requests could disrupt TLS termination, enable man-in-the-middle attacks if bound to wrong hosts, or exhaust Let's Encrypt rate limits.

From the tool's definition Tool name 'request_certificate' combined with server description stating it 'request[s] Let's Encrypt SSL certificates' indicates creation of new certificate resources.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

request_certificate Rate-limited

request_certificate 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": {
    "request_certificate": {
      "limits": [
        {
          "counter": "request_certificate_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 Nginx Proxy Manager MCP, so you can run agents against it safely.

FAQ

Questions about request_certificate

What does the request_certificate tool do? +

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

How do I enforce a policy on request_certificate? +

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

What risk level is request_certificate? +

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

Can I rate-limit request_certificate? +

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

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

request_certificate is provided by the Nginx Proxy Manager MCP server (verybigsad/nginx-proxy-manager-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.