open_url_on_device · MCP Emulator Controller MCP

WHAT IT DOES

What open_url_on_device does on MCP Emulator Controller

AI agents invoke open_url_on_device to trigger actions in MCP Emulator Controller. 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 open_url_on_device needs a policy

This tool triggers an external operation on the device by opening a URL in the browser. The effects depend on the URL argument — navigating to a URL initiates a network request and browser action on the device, which is an execution of an external operation. It is not a simple read (it causes a side effect on the device), and it could be misused to open malicious URLs, phishing pages, or trigger drive-by downloads.

From the tool's definition Open URL in default browser on device

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

open_url_on_device Rate-limited

open_url_on_device 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": {
    "open_url_on_device": {
      "limits": [
        {
          "counter": "open_url_on_device_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 Emulator Controller, so you can run agents against it safely.

FAQ

Questions about open_url_on_device

What does the open_url_on_device tool do? +

Open URL in default browser on device. It is categorised as a Execute tool in the MCP Emulator Controller MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on open_url_on_device? +

Register the MCP Emulator Controller MCP server in PolicyLayer and add a rule for open_url_on_device: 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 Emulator Controller. Nothing to install.

What risk level is open_url_on_device? +

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

Can I rate-limit open_url_on_device? +

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

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

open_url_on_device is provided by the MCP Emulator Controller MCP server (teemo4621/mcp-emulator-controller). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.