screen_learn_hover · Screen Agent MCP: Risk & Policy

WHAT IT DOES

What screen_learn_hover does on Screen Agent

AI agents invoke screen_learn_hover to trigger actions in Screen Agent. 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 screen_learn_hover needs a policy

This tool performs a mouse hover action on the desktop UI as part of a learning/automation system. Hovering is an active desktop interaction (Execute category) that can trigger UI state changes (tooltips, dropdowns, dynamic content).

From the tool's definition '鼠标悬停学习UI交互效果' (learn UI interaction effects via mouse hover) — triggers mouse hover actions on the desktop

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

screen_learn_hover Rate-limited

screen_learn_hover 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": {
    "screen_learn_hover": {
      "limits": [
        {
          "counter": "screen_learn_hover_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 Screen Agent, so you can run agents against it safely.

FAQ

Questions about screen_learn_hover

What does the screen_learn_hover tool do? +

通过鼠标悬停学习UI交互效果。. It is categorised as a Execute tool in the Screen Agent MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on screen_learn_hover? +

Register the Screen Agent MCP server in PolicyLayer and add a rule for screen_learn_hover: 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 Screen Agent. Nothing to install.

What risk level is screen_learn_hover? +

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

Can I rate-limit screen_learn_hover? +

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

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

screen_learn_hover is provided by the Screen Agent MCP server (lqszhsp/screen-agent). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.