focus_element

Focus a DOM element. Args: node_id: Node ID of the element to focus Returns: Success status of the focus operation

SERVERChrome Devtools SOURCEbenjaminr/chrome-devtools-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/benjaminr-chrome-devtools-mcp/focus-element.md

WHAT IT DOES

What focus_element does on Chrome Devtools

AI agents invoke focus_element to trigger actions in Chrome Devtools. 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 focus_element is rated High

Focusing a DOM element triggers a browser action (focus event) that can activate UI components, trigger JavaScript event handlers, and change browser state. It's an external browser operation rather than a pure read or data write. The blast radius is low since focusing an element is generally non-destructive, but it can trigger event-driven behavior depending on the page's JavaScript.

From the tool's definition Focus a DOM element... Success status of the focus operation

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs focus_element safely

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

focus_element Rate-limited

focus_element 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": {
    "focus_element": {
      "limits": [
        {
          "counter": "focus_element_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 Chrome Devtools, apply this rule, and every focus_element call is checked against it from then on.

FAQ

Questions about focus_element

What does the focus_element tool do? +

Focus a DOM element. Args: node_id: Node ID of the element to focus Returns: Success status of the focus operation. It is categorised as a Execute tool in the Chrome Devtools MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on focus_element? +

Register the Chrome Devtools MCP server in PolicyLayer and add a rule for focus_element: 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 Chrome Devtools. Nothing to install.

What risk level is focus_element? +

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

Can I rate-limit focus_element? +

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

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

focus_element is provided by the Chrome Devtools MCP server (benjaminr/chrome-devtools-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Chrome Devtools, and thousands of servers like it.

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Guides

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