set_brightness · Sysprobe MCP: Risk & Policy

WHAT IT DOES

What set_brightness does on Sysprobe

AI agents invoke set_brightness to trigger actions in Sysprobe. 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 set_brightness needs a policy

This tool performs a mutating system action — changing display brightness — which triggers an external hardware operation. It doesn't delete data (not Destructive) or involve finances (not Financial), but it does alter system state by controlling hardware settings. The server description notes 'mutating actions' require explicit flags, confirming this is a write/execute-class operation.

From the tool's definition [ACTION] Set display brightness to a percentage (1–100)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_brightness Rate-limited

set_brightness 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": {
    "set_brightness": {
      "limits": [
        {
          "counter": "set_brightness_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 Sysprobe, so you can run agents against it safely.

FAQ

Questions about set_brightness

What does the set_brightness tool do? +

[ACTION] Set display brightness to a percentage (1–100). It is categorised as a Execute tool in the Sysprobe MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on set_brightness? +

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

What risk level is set_brightness? +

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

Can I rate-limit set_brightness? +

Yes. Add a rate_limit block to the set_brightness 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_brightness completely? +

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

set_brightness is provided by the Sysprobe MCP server (raindancer118/sysprobe-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.