vnc_set_clipboard · VNC MCP Server MCP: Risk & Policy

WHAT IT DOES

What vnc_set_clipboard does on VNC MCP Server

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

WHY IT NEEDS A POLICY

Why vnc_set_clipboard needs a policy

This tool modifies data (clipboard contents) on a remote machine in a reversible manner. While clipboard manipulation could enable credential theft or data exfiltration if abused, the action itself is reversible and doesn't permanently destroy data or execute arbitrary code. However, given the context of VNC remote desktop control, this poses moderate risk as clipboard is often used to transfer sensitive information.

From the tool's definition Tool name 'vnc_set_clipboard' and description 'Set the remote clipboard' indicate modification of clipboard data on a remote system via VNC control.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vnc_set_clipboard Rate-limited

vnc_set_clipboard 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": {
    "vnc_set_clipboard": {
      "limits": [
        {
          "counter": "vnc_set_clipboard_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 VNC MCP Server, so you can run agents against it safely.

FAQ

Questions about vnc_set_clipboard

What does the vnc_set_clipboard tool do? +

Set the remote clipboard. It is categorised as a Write tool in the VNC 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 vnc_set_clipboard? +

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

What risk level is vnc_set_clipboard? +

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

Can I rate-limit vnc_set_clipboard? +

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

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

vnc_set_clipboard is provided by the VNC MCP Server MCP server (volkan-m/vnc-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.