reboot_domain · Libvirt MCP: Risk & Policy

WHAT IT DOES

What reboot_domain does on Libvirt

AI agents invoke reboot_domain to trigger actions in Libvirt. 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 reboot_domain needs a policy

Rebooting a VM triggers an external lifecycle operation on a running virtual machine. It is not a simple read, nor does it destroy data, but it interrupts running workloads and causes a restart — an Execute-level action. Misuse could disrupt services running on the VM.

From the tool's definition Request graceful ACPI reboot of a running domain

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

reboot_domain Rate-limited

reboot_domain 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": {
    "reboot_domain": {
      "limits": [
        {
          "counter": "reboot_domain_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 Libvirt, so you can run agents against it safely.

FAQ

Questions about reboot_domain

What does the reboot_domain tool do? +

Request graceful ACPI reboot of a running domain. It is categorised as a Execute tool in the Libvirt MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on reboot_domain? +

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

What risk level is reboot_domain? +

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

Can I rate-limit reboot_domain? +

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

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

reboot_domain is provided by the Libvirt MCP server (rzippert/libvirt-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.