set_device_value · Smart Home Control MCP Server MCP

WHAT IT DOES

What set_device_value does on Smart Home Control MCP Server

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

WHY IT NEEDS A POLICY

Why set_device_value needs a policy

This tool writes a new value to a smart home device parameter (e.g., brightness, temperature, fan speed). It creates or modifies device state reversibly, as parameters can be changed again. Misuse could cause discomfort (e.g., extreme temperatures) or minor safety concerns, but effects are generally reversible, warranting medium severity.

From the tool's definition "Set a specific parameter for a device" — modifies device state/configuration

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_device_value Rate-limited

set_device_value 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_device_value": {
      "limits": [
        {
          "counter": "set_device_value_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 Smart Home Control MCP Server, so you can run agents against it safely.

FAQ

Questions about set_device_value

What does the set_device_value tool do? +

Set a specific parameter for a device. It is categorised as a Write tool in the Smart Home Control MCP Server 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_device_value? +

Register the Smart Home Control MCP Server MCP server in PolicyLayer and add a rule for set_device_value: 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 Smart Home Control MCP Server. Nothing to install.

What risk level is set_device_value? +

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

Can I rate-limit set_device_value? +

Yes. Add a rate_limit block to the set_device_value 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_device_value completely? +

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

set_device_value is provided by the Smart Home Control MCP Server MCP server (surya443/smart-home-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.