open_1wire · Buspirate MCP: Risk & Policy

WHAT IT DOES

What open_1wire does on Buspirate

AI agents use open_1wire to create or update resources in Buspirate — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Buspirate environment.

WHY IT NEEDS A POLICY

Why open_1wire needs a policy

Opening a 1-Wire connection initializes and configures hardware interface state, which is a reversible write/setup operation. It doesn't read data, execute commands on a target device, or destroy data, but it does establish a new active connection resource. Severity is medium because misuse could interfere with hardware devices on the 1-Wire bus.

From the tool's definition Open a 1-Wire connection and start an engagement

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

open_1wire Rate-limited

open_1wire 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": {
    "open_1wire": {
      "limits": [
        {
          "counter": "open_1wire_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 Buspirate, so you can run agents against it safely.

FAQ

Questions about open_1wire

What does the open_1wire tool do? +

Open a 1-Wire connection and start an engagement. It is categorised as a Write tool in the Buspirate MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on open_1wire? +

Register the Buspirate MCP server in PolicyLayer and add a rule for open_1wire: 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 open_1wire? +

open_1wire is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit open_1wire? +

Yes. Add a rate_limit block to the open_1wire 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 open_1wire completely? +

Set action: deny in the PolicyLayer policy for open_1wire. 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 open_1wire? +

open_1wire 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.