element_hover · MCP Playwright Server MCP: Risk & Policy

WHAT IT DOES

What element_hover does on MCP Playwright Server

AI agents invoke element_hover to trigger actions in MCP Playwright Server. 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 element_hover needs a policy

Hovering over an element is a browser action that executes a UI interaction. While it doesn't modify persistent data, it triggers external operations in the browser (e.g., revealing menus, loading dynamic content, firing JavaScript events). This falls under Execute as it runs browser actions whose effects depend on the target element.

From the tool's definition 'Hover over an element' - triggers a browser interaction/action via Playwright automation that causes external browser state changes (hover effects, tooltips, dynamic content loading)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

element_hover Rate-limited

element_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": {
    "element_hover": {
      "limits": [
        {
          "counter": "element_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 MCP Playwright Server, so you can run agents against it safely.

FAQ

Questions about element_hover

What does the element_hover tool do? +

Hover over an element using various locator strategies. Locator types (in recommended priority order): -. It is categorised as a Execute tool in the MCP Playwright Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on element_hover? +

Register the MCP Playwright Server MCP server in PolicyLayer and add a rule for element_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 MCP Playwright Server. Nothing to install.

What risk level is element_hover? +

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

Can I rate-limit element_hover? +

Yes. Add a rate_limit block to the element_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 element_hover completely? +

Set action: deny in the PolicyLayer policy for element_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 element_hover? +

element_hover is provided by the MCP Playwright Server MCP server (j0hanz/playwright-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.