hold_in_reset · Pymcuprog MCP: Risk & Policy

WHAT IT DOES

What hold_in_reset does on Pymcuprog

AI agents invoke hold_in_reset to trigger actions in Pymcuprog. 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 hold_in_reset needs a policy

This tool triggers an external hardware operation on a microcontroller (asserting reset signal), which is an active control action affecting a physical device. It is not a simple read, nor does it permanently delete data, but it does execute an external operation that disrupts the target device's normal operation. Misuse could cause unintended downtime or interrupt running processes on the microcontroller.

From the tool's definition Hold the target device in reset

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

hold_in_reset Rate-limited

hold_in_reset 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": {
    "hold_in_reset": {
      "limits": [
        {
          "counter": "hold_in_reset_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 Pymcuprog, so you can run agents against it safely.

FAQ

Questions about hold_in_reset

What does the hold_in_reset tool do? +

Hold the target device in reset. It is categorised as a Execute tool in the Pymcuprog MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on hold_in_reset? +

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

What risk level is hold_in_reset? +

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

Can I rate-limit hold_in_reset? +

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

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

hold_in_reset is provided by the Pymcuprog MCP server (lucasgerads/pymcuprog-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.