browser_close · Limetest MCP Server MCP: Risk & Policy

WHAT IT DOES

What browser_close does on Limetest MCP Server

AI agents invoke browser_close to trigger actions in Limetest MCP 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 browser_close needs a policy

Closing a browser page is an external operation that ends the current page session. While not destructive to persistent data, it triggers a browser-level action with side effects (loss of unsaved state, termination of the page context). It fits Execute as it performs an operation on an external system (the browser) whose effects depend on current state.

From the tool's definition 'Close the page' — terminates a browser page/session, an external browser operation that cannot be trivially undone without re-navigating

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

browser_close Rate-limited

browser_close 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": {
    "browser_close": {
      "limits": [
        {
          "counter": "browser_close_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 Limetest MCP Server, so you can run agents against it safely.

FAQ

Questions about browser_close

What does the browser_close tool do? +

Close the page. It is categorised as a Execute tool in the Limetest MCP 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 browser_close? +

Register the Limetest MCP Server MCP server in PolicyLayer and add a rule for browser_close: 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 Limetest MCP Server. Nothing to install.

What risk level is browser_close? +

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

Can I rate-limit browser_close? +

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

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

browser_close is provided by the Limetest MCP Server MCP server (m2rads/limetest-arch). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.