resize_vm_resources · Virtualbox MCP Server MCP

WHAT IT DOES

What resize_vm_resources does on Virtualbox MCP Server

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

WHY IT NEEDS A POLICY

Why resize_vm_resources needs a policy

This tool modifies VM resource configuration (CPU, RAM, GUI settings), which is a reversible write operation. However, it also triggers a reboot of running VMs as a side effect, which can cause service interruption. The blast radius is high because misuse could disrupt running workloads by causing unexpected reboots or misconfiguring critical VM resources.

From the tool's definition Modifies VM CPU/RAM/GUI settings. Triggers a reboot if the VM is running.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

resize_vm_resources Rate-limited

resize_vm_resources 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": {
    "resize_vm_resources": {
      "limits": [
        {
          "counter": "resize_vm_resources_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 Virtualbox MCP Server, so you can run agents against it safely.

FAQ

Questions about resize_vm_resources

What does the resize_vm_resources tool do? +

Modifies VM CPU/RAM/GUI settings. Triggers a reboot if the VM is running. It is categorised as a Write tool in the Virtualbox MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on resize_vm_resources? +

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

What risk level is resize_vm_resources? +

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

Can I rate-limit resize_vm_resources? +

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

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

resize_vm_resources is provided by the Virtualbox MCP Server MCP server (usemanusai/virtualbox-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.