navigate_page · JS Reverse MCP: Risk & Policy

WHAT IT DOES

What navigate_page does on JS Reverse MCP

AI agents invoke navigate_page to trigger actions in JS Reverse MCP. 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 navigate_page needs a policy

Navigation to arbitrary URLs constitutes execution of external operations through the browser, as URLs can trigger code execution, network requests with side effects, and JavaScript evaluation on remote domains.

From the tool's definition Tool performs page navigation via 'navigate_page' to arbitrary URLs with 'Navigates the currently selected page to a URL' and can execute browser operations like 'back/forward/reload navigation'.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

navigate_page Rate-limited

navigate_page 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": {
    "navigate_page": {
      "limits": [
        {
          "counter": "navigate_page_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 JS Reverse MCP, so you can run agents against it safely.

FAQ

Questions about navigate_page

What does the navigate_page tool do? +

Navigates the currently selected page to a URL, or performs back/forward/reload navigation. Waits for DOMContentLoaded event (not full page load). Default timeout is 10 seconds. It is categorised as a Execute tool in the JS Reverse MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on navigate_page? +

Register the JS Reverse MCP server in PolicyLayer and add a rule for navigate_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 JS Reverse MCP. Nothing to install.

What risk level is navigate_page? +

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

Can I rate-limit navigate_page? +

Yes. Add a rate_limit block to the navigate_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 navigate_page completely? +

Set action: deny in the PolicyLayer policy for navigate_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 navigate_page? +

navigate_page is provided by the JS Reverse MCP server (noone-hub/jsreverser-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.