write_clipboard · Computer Use MCP Server MCP: Risk & Policy

WHAT IT DOES

What write_clipboard does on Computer Use MCP Server

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

WHY IT NEEDS A POLICY

Why write_clipboard needs a policy

This tool creates or modifies clipboard contents reversibly. While clipboard writes are not destructive (can be undone by overwriting), they can be misused to inject malicious content into paste operations, interfere with user workflows, or exfiltrate data by replacing clipboard contents.

From the tool's definition write_clipboard: 'Write text to the clipboard' — explicitly modifies clipboard state, a system resource accessible to the user's applications.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

write_clipboard Rate-limited

write_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": {
    "write_clipboard": {
      "limits": [
        {
          "counter": "write_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 Computer Use MCP Server, so you can run agents against it safely.

FAQ

Questions about write_clipboard

What does the write_clipboard tool do? +

Write text to the clipboard. It is categorised as a Write tool in the Computer Use 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 write_clipboard? +

Register the Computer Use MCP Server MCP server in PolicyLayer and add a rule for write_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 Computer Use MCP Server. Nothing to install.

What risk level is write_clipboard? +

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

Can I rate-limit write_clipboard? +

Yes. Add a rate_limit block to the write_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 write_clipboard completely? +

Set action: deny in the PolicyLayer policy for write_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 write_clipboard? +

write_clipboard is provided by the Computer Use MCP Server MCP server (syedazharmbnr1/computer-use-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.