set_security_mode · Nest Protect MCP Server MCP

WHAT IT DOES

What set_security_mode does on Nest Protect MCP Server

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

WHY IT NEEDS A POLICY

Why set_security_mode needs a policy

This tool modifies the security mode of smoke/CO detectors. Changing security mode is a reversible write operation (it can be changed back), but the blast radius is high because misconfiguring security mode on life-safety devices (smoke and CO detectors) could suppress alerts or change detection sensitivity, potentially endangering occupants.

From the tool's definition "Set Guard Security Mode" — sets/configures a security mode on Nest Protect devices

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_security_mode Rate-limited

set_security_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_security_mode": {
      "limits": [
        {
          "counter": "set_security_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 Nest Protect MCP Server, so you can run agents against it safely.

FAQ

Questions about set_security_mode

What does the set_security_mode tool do? +

Set Guard Security Mode. It is categorised as a Write tool in the Nest Protect 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_security_mode? +

Register the Nest Protect MCP Server MCP server in PolicyLayer and add a rule for set_security_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 Nest Protect MCP Server. Nothing to install.

What risk level is set_security_mode? +

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

Can I rate-limit set_security_mode? +

Yes. Add a rate_limit block to the set_security_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_security_mode completely? +

Set action: deny in the PolicyLayer policy for set_security_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_security_mode? +

set_security_mode is provided by the Nest Protect MCP Server MCP server (sandraschi/nest-protect-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.