set_away_mode · Home Controller MCP: Risk & Policy

WHAT IT DOES

What set_away_mode does on Home Controller

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

WHY IT NEEDS A POLICY

Why set_away_mode needs a policy

Setting away mode changes the operational configuration of connected smart home devices (appliances, sauna, water monitor, etc.). This is a reversible state change — it can be toggled back — so it falls under Write rather than Execute or Destructive.

From the tool's definition 'Enable or disable away mode' — toggles a smart home operational mode, modifying device/system state reversibly

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_away_mode Rate-limited

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

FAQ

Questions about set_away_mode

What does the set_away_mode tool do? +

Enable or disable away mode. It is categorised as a Write tool in the Home Controller MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_away_mode? +

Register the Home Controller MCP server in PolicyLayer and add a rule for set_away_mode: 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 set_away_mode? +

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

Can I rate-limit set_away_mode? +

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

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

set_away_mode 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.