start_system_vm · CloudStack MCP Server MCP: Risk & Policy

WHAT IT DOES

What start_system_vm does on CloudStack MCP Server

AI agents invoke start_system_vm to trigger actions in CloudStack MCP Server. 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 start_system_vm needs a policy

Starting a system virtual machine is an execute action—it runs a command that changes the state of CloudStack infrastructure. While not destructive (reversible via stop_system_vm) and not immediately catastrophic in isolation, it has significant blast radius if misused by an agent (could start unintended VMs, trigger cascading infrastructure changes, or consume resources).

From the tool's definition Tool name 'start_system_vm' and description 'Start a system virtual machine' indicate execution of an operational command that triggers external infrastructure state changes.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

start_system_vm Rate-limited

start_system_vm 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": {
    "start_system_vm": {
      "limits": [
        {
          "counter": "start_system_vm_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 CloudStack MCP Server, so you can run agents against it safely.

FAQ

Questions about start_system_vm

What does the start_system_vm tool do? +

Start a system virtual machine. It is categorised as a Execute tool in the CloudStack MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on start_system_vm? +

Register the CloudStack MCP Server MCP server in PolicyLayer and add a rule for start_system_vm: 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 CloudStack MCP Server. Nothing to install.

What risk level is start_system_vm? +

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

Can I rate-limit start_system_vm? +

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

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

start_system_vm is provided by the CloudStack MCP Server MCP server (mozg31337/cloudstack-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.