set_clipboard · MacWright MCP: Risk & Policy

WHAT IT DOES

What set_clipboard does on MacWright

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

WHY IT NEEDS A POLICY

Why set_clipboard needs a policy

This tool modifies system clipboard state, which is reversible but has significant security implications. An AI agent could overwrite clipboard contents to inject malicious text or HTML, affecting subsequent paste operations by the user. This represents a meaningful Write-class operation with potentially harmful consequences (e.g., replacing legitimate data with phishing links or commands).

From the tool's definition Set the system clipboard contents. Supports plain text and HTML.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_clipboard Rate-limited

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": {
    "set_clipboard": {
      "limits": [
        {
          "counter": "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 MacWright, so you can run agents against it safely.

FAQ

Questions about set_clipboard

What does the set_clipboard tool do? +

Set the system clipboard contents. Supports plain text and HTML. When HTML is provided, both HTML and plain text are set so paste works in both rich and plain text editors. It is categorised as a Write tool in the MacWright MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_clipboard? +

Register the MacWright MCP server in PolicyLayer and add a rule for 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 MacWright. Nothing to install.

What risk level is set_clipboard? +

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

Can I rate-limit set_clipboard? +

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

Set action: deny in the PolicyLayer policy for 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 set_clipboard? +

set_clipboard is provided by the MacWright MCP server (ruchit-p/macwright). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.