close_page

THE RISK

Critical Risk

Why close_page needs a policy

Closing a browser page is an irreversible action that destroys the current page state, any unsaved work, and active sessions. The page cannot be restored once closed, making this a destructive operation. Severity is medium because while it disrupts the current browser session, it doesn't affect persistent data outside the browser.

From the tool's definition Closes the page by its index

Documented attack patterns abuse exactly the kind of access close_page gives an agent:

POLICY

How to control close_page

PolicyLayer is an MCP gateway — it sits between your AI agents and ReverseCraft DevTools MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for close_page:

policy.json

{
  "version": "1",
  "default": "deny",
  "hide": [
    "close_page"
  ]
}

close_page disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.

Create a free account and register ReverseCraft DevTools MCP — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RESTRICT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More ReverseCraft DevTools MCP tools

Destructive clear_cookies Clear browser cookies for all sites or a specific domain. Destructive clear_persistent_scripts Remove all registered persistent scripts for the current page at once. This is useful for Destructive clear_script_replacements Remove all script replacement rules for the current page. Destructive remove_persistent_script Remove a previously registered persistent script by its identifier. After removal, the sc Destructive remove_script_replacement Remove a script replacement rule by its ID. Destructive remove_xhr_breakpoint Remove a previously set XHR/Fetch breakpoint by its URL pattern, or remove all XHR breakpo Execute navigate_page Navigates the currently selected page to a URL. Execute new_page Creates a new page

All 46 ReverseCraft DevTools MCP tools →

Destructive tools on other servers

Android Forensics ADB MCP Server create_full_backup 0xarchive web3_revoke_key Frida Game Hacking MCP clear_scan cPanel MCP Server clear_spam_box

Go deeper

Critical-risk tools in ReverseCraft DevTools MCP → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Blast radius → How much damage one compromised or confused agent can do — and how to bound it.
Tool call approval → Approval gates on individual tool calls: auto-allow, prompt, or deny.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about close_page

What does the close_page tool do? +

Closes the page by its index. The last open page cannot be closed. It is categorised as a Destructive tool in the ReverseCraft DevTools MCP MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.

How do I enforce a policy on close_page? +

Register the ReverseCraft DevTools MCP server in PolicyLayer and add a rule for close_page: 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 ReverseCraft DevTools MCP. Nothing to install.

What risk level is close_page? +

close_page is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit close_page? +

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

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

close_page is provided by the ReverseCraft DevTools MCP server (reverse-craft/rc-devtools-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every ReverseCraft DevTools MCP tool call.

Start from ReverseCraft DevTools MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →