open_url

Navigate the current tab to a URL using real-browser JS navigation.

SERVERAgent Browser SOURCE335234131/agent-browser-mcp

High RISK CLASS

Category Execute

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/335234131-agent-browser-mcp/open-url.md

WHAT IT DOES

What open_url does on Agent Browser

AI agents invoke open_url to trigger actions in Agent Browser. 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.

RISK

Why open_url is rated High

This tool executes a browser navigation action by running JavaScript to redirect the current tab to an arbitrary URL. It triggers an external operation (navigation) whose effects depend on the URL argument — it could load malicious pages, trigger downloads, bypass security controls, or exfiltrate data via navigation.

From the tool's definition Navigate the current tab to a URL using real-browser JS navigation

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs open_url safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Agent Browser, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For open_url, this is the rule to start with:

open_url Rate-limited

open_url 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": {
      "limits": [
        {
          "counter": "open_url_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Agent Browser, apply this rule, and every open_url call is checked against it from then on.

FAQ

Questions about open_url

What does the open_url tool do? +

Navigate the current tab to a URL using real-browser JS navigation. It is categorised as a Execute tool in the Agent Browser 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? +

Register the Agent Browser MCP server in PolicyLayer and add a rule for open_url: 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 Agent Browser. Nothing to install.

What risk level is open_url? +

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

Can I rate-limit open_url? +

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

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

open_url is provided by the Agent Browser MCP server (335234131/agent-browser-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Agent Browser, and thousands of servers like it.

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