buzz_opener · Nuki MCP: Risk & Policy

WHAT IT DOES

What buzz_opener does on Nuki

AI agents invoke buzz_opener to trigger actions in Nuki. 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 buzz_opener needs a policy

This tool executes a command that triggers physical hardware (electric strike/buzz-in mechanism) with immediate real-world effects. While not permanently destructive, it grants building access and cannot be easily undone once activated. It falls under Execute rather than Write because it invokes external hardware operations whose effects are determined by the state of the physical system.

From the tool's definition Tool description states 'Trigger the Nuki Opener electric strike (buzz-in)' - directly activates a physical device that controls building access by unlocking entry doors electronically.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

buzz_opener Rate-limited

buzz_opener 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": {
    "buzz_opener": {
      "limits": [
        {
          "counter": "buzz_opener_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 Nuki, so you can run agents against it safely.

FAQ

Questions about buzz_opener

What does the buzz_opener tool do? +

Trigger the Nuki Opener electric strike (buzz-in). It is categorised as a Execute tool in the Nuki MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on buzz_opener? +

Register the Nuki MCP server in PolicyLayer and add a rule for buzz_opener: 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 Nuki. Nothing to install.

What risk level is buzz_opener? +

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

Can I rate-limit buzz_opener? +

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

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

buzz_opener is provided by the Nuki MCP server (sandraschi/nuki-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.