set_capture_device · Mcp Serial Hid Kvm MCP: Risk & Policy

WHAT IT DOES

What set_capture_device does on Mcp Serial Hid Kvm

AI agents invoke set_capture_device to trigger actions in Mcp Serial Hid Kvm. 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 set_capture_device needs a policy

This tool triggers an external hardware operation — switching and reopening a capture device — which has side effects on the system's KVM capture state. It's not purely reading data, nor is it destructive or financial. It executes a state-change operation on physical hardware, fitting the Execute category. Misuse could disrupt the active screen capture session, hence medium severity.

From the tool's definition Switch the active capture device by index or path... Reopens the capture device.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_capture_device Rate-limited

set_capture_device 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": {
    "set_capture_device": {
      "limits": [
        {
          "counter": "set_capture_device_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 Mcp Serial Hid Kvm, so you can run agents against it safely.

FAQ

Questions about set_capture_device

What does the set_capture_device tool do? +

Switch the active capture device by index or path. Use list_capture_devices first to see available options. Reopens the capture device. It is categorised as a Execute tool in the Mcp Serial Hid Kvm MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on set_capture_device? +

Register the Mcp Serial Hid Kvm MCP server in PolicyLayer and add a rule for set_capture_device: 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 Mcp Serial Hid Kvm. Nothing to install.

What risk level is set_capture_device? +

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

Can I rate-limit set_capture_device? +

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

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

set_capture_device is provided by the Mcp Serial Hid Kvm MCP server (sunasaji/mcp-serial-hid-kvm). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.