network_route · MCP Playwright Server MCP: Risk & Policy

WHAT IT DOES

What network_route does on MCP Playwright Server

AI agents invoke network_route 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 network_route needs a policy

This tool intercepts and modifies network requests in-flight, allowing an AI agent to tamper with traffic, inject malicious responses, redirect requests, or manipulate data sent/received by the browser. This is an active execution-level capability with significant blast radius—it could be used to perform MITM-style attacks within the browser session, alter authentication flows, or corrupt data.

From the tool's definition Intercept and modify network requests matching a URL pattern

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

network_route Rate-limited

network_route 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": {
    "network_route": {
      "limits": [
        {
          "counter": "network_route_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 network_route

What does the network_route tool do? +

Intercept and modify network requests matching a URL pattern. Actions: -. 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 network_route? +

Register the MCP Playwright Server MCP server in PolicyLayer and add a rule for network_route: 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 network_route? +

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

Can I rate-limit network_route? +

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

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

network_route 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.