toggle_light · Home Controller MCP: Risk & Policy

WHAT IT DOES

What toggle_light does on Home Controller

AI agents invoke toggle_light to trigger actions in Home Controller. 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 toggle_light needs a policy

This tool executes a real-world physical action by toggling a smart home device's light state. It spans Write (changing state) and Execute (triggering an external operation on physical hardware). Since it controls a physical device with immediate real-world effects, Execute is the most appropriate category.

From the tool's definition Toggle the sauna light on/off — triggers an external physical operation on a smart home device (HUUM sauna light)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

toggle_light Rate-limited

toggle_light 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": {
    "toggle_light": {
      "limits": [
        {
          "counter": "toggle_light_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 Home Controller, so you can run agents against it safely.

FAQ

Questions about toggle_light

What does the toggle_light tool do? +

Toggle the sauna light on/off. It is categorised as a Execute tool in the Home Controller MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on toggle_light? +

Register the Home Controller MCP server in PolicyLayer and add a rule for toggle_light: 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 Home Controller. Nothing to install.

What risk level is toggle_light? +

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

Can I rate-limit toggle_light? +

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

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

toggle_light is provided by the Home Controller MCP server (winsthuang/home-controller). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.