prompt_user · Apple Notifier MCP: Risk & Policy

WHAT IT DOES

What prompt_user does on Apple Notifier

AI agents invoke prompt_user to trigger actions in Apple Notifier. 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 prompt_user needs a policy

This tool triggers an external UI operation — displaying a native macOS dialog prompt — which is an interactive action with effects beyond the process itself. It involves executing a system-level dialog (likely via AppleScript or similar), which qualifies as Execute. Misuse could be used to social-engineer or confuse users by displaying unexpected prompts, giving it medium severity.

From the tool's definition Display a dialog prompt to get user input

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

prompt_user Rate-limited

prompt_user 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": {
    "prompt_user": {
      "limits": [
        {
          "counter": "prompt_user_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 Apple Notifier, so you can run agents against it safely.

FAQ

Questions about prompt_user

What does the prompt_user tool do? +

Display a dialog prompt to get user input. It is categorised as a Execute tool in the Apple Notifier MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on prompt_user? +

Register the Apple Notifier MCP server in PolicyLayer and add a rule for prompt_user: 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 Apple Notifier. Nothing to install.

What risk level is prompt_user? +

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

Can I rate-limit prompt_user? +

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

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

prompt_user is provided by the Apple Notifier MCP server (piatra-automation/apple-notifier-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.