proxmox_exec · Homelab MCP: Risk & Policy

WHAT IT DOES

What proxmox_exec does on Homelab

AI agents invoke proxmox_exec to trigger actions in Homelab. 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 proxmox_exec needs a policy

This tool allows arbitrary shell command execution on a Proxmox hypervisor host. Although the description claims 'destructive commands are blocked,' command execution on infrastructure (especially at host level) poses high risk: an AI agent could misconfigure networking, storage, or VMs; cause unintended resource consumption; or exploit filtering gaps.

From the tool's definition Tool explicitly states 'Execute a shell command on the Proxmox host via SSH' and is described for 'disk operations and host-level administration.' This is code/command execution on a critical infrastructure node.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

proxmox_exec Rate-limited

proxmox_exec 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": {
    "proxmox_exec": {
      "limits": [
        {
          "counter": "proxmox_exec_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 Homelab, so you can run agents against it safely.

FAQ

Questions about proxmox_exec

What does the proxmox_exec tool do? +

Execute a shell command on the Proxmox host via SSH. Use for disk operations and host-level administration. Destructive commands are blocked. It is categorised as a Execute tool in the Homelab MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on proxmox_exec? +

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

What risk level is proxmox_exec? +

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

Can I rate-limit proxmox_exec? +

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

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

proxmox_exec is provided by the Homelab MCP server (nainounen/homelab-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.