scout_hover · Scout MCP: Risk & Policy

WHAT IT DOES

What scout_hover does on Scout

AI agents invoke scout_hover to trigger actions in Scout. 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 scout_hover needs a policy

Hovering is a browser action that can trigger UI side effects (e.g., tooltips, dropdowns, dynamic content loading, or JavaScript event handlers). It is an external operation executed in a real browser session, placing it in the Execute category. Blast radius is low since hovering alone rarely causes irreversible changes, but it can trigger meaningful page state changes.

From the tool's definition 'Hover over an element by its snapshot ID' — triggers a browser interaction/action on a live web page

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

scout_hover Rate-limited

scout_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": {
    "scout_hover": {
      "limits": [
        {
          "counter": "scout_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 Scout, so you can run agents against it safely.

FAQ

Questions about scout_hover

What does the scout_hover tool do? +

Hover over an element by its snapshot ID. It is categorised as a Execute tool in the Scout MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on scout_hover? +

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

What risk level is scout_hover? +

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

Can I rate-limit scout_hover? +

Yes. Add a rate_limit block to the scout_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 scout_hover completely? +

Set action: deny in the PolicyLayer policy for scout_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 scout_hover? +

scout_hover is provided by the Scout MCP server (lautrek/scout). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.