AI agents invoke playwright_hover to trigger actions in MCP Playwright CDP. 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.
Hovering triggers browser UI interactions (tooltips, dropdowns, hover-state events) that can cause side effects in the DOM or trigger external operations depending on the page. It is a browser action executed via Playwright/CDP, placing it in the Execute category. Severity is medium because hovering alone rarely causes irreversible harm, but in an agentic context it could reveal or trigger sensitive UI elements.
From the tool's definition Hover an element on the page
Documented attack patterns abuse exactly the kind of access playwright_hover gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Playwright CDP, and nothing reaches the server without passing your rules. This is the rule we recommend for playwright_hover:
{
"version": "1",
"default": "deny",
"tools": {
"playwright_hover": {
"limits": [
{
"counter": "playwright_hover_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}playwright_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.
Free to start. No card required.
Hover an element on the page. It is categorised as a Execute tool in the MCP Playwright CDP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the MCP Playwright CDP MCP server in PolicyLayer and add a rule for playwright_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 CDP. Nothing to install.
playwright_hover is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the playwright_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.
Set action: deny in the PolicyLayer policy for playwright_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.
playwright_hover is provided by the MCP Playwright CDP MCP server (lars-hagen/mcp-playwright-cdp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from MCP Playwright CDP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
12 MCP Playwright CDP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.