set_voltage · Buspirate MCP: Risk & Policy

WHAT IT DOES

What set_voltage does on Buspirate

AI agents invoke set_voltage to trigger actions in Buspirate. 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_voltage needs a policy

This tool controls hardware power supply parameters on a physical device. Setting incorrect voltage or current limits can damage connected hardware components irreversibly, though the action itself is a configuration/execution operation rather than a data deletion. It triggers an external hardware operation whose effects depend on arguments, making Execute the appropriate category.

From the tool's definition Set power supply voltage (0.8-5.0V) and current limit (0-500mA)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_voltage Rate-limited

set_voltage 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_voltage": {
      "limits": [
        {
          "counter": "set_voltage_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 Buspirate, so you can run agents against it safely.

FAQ

Questions about set_voltage

What does the set_voltage tool do? +

Set power supply voltage (0.8-5.0V) and current limit (0-500mA). It is categorised as a Execute tool in the Buspirate 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_voltage? +

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

What risk level is set_voltage? +

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

Can I rate-limit set_voltage? +

Yes. Add a rate_limit block to the set_voltage 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_voltage completely? +

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

set_voltage is provided by the Buspirate MCP server (mplogas/buspirate-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.