new_tab

What new_tab does on Browser

AI agents invoke new_tab to trigger actions in 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.

Why new_tab is rated High

Creating a new tab with a specified URL is an Execute-class action because it triggers an external browser operation whose effects depend on the URL argument. While opening a tab alone is less severe than code execution, in the context of an MCP server for 'browser automation,' this tool can be chained with execute_script and other siblings to perform complex automated actions.

From the tool's definition Tool opens a new browser tab with a URL. Combined with sibling tools like execute_script, this is part of a browser automation toolkit that can trigger external operations and navigate to arbitrary destinations.

The rule that runs new_tab safely

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

{
  "version": "1",
  "default": "deny",
  "tools": {
    "new_tab": {
      "limits": [
        {
          "counter": "new_tab_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

Questions about new_tab