browser_focus_tab

THE RISK

High Risk

Based on the tool name and the server's purpose of browser automation, this tool likely switches focus to a specific browser tab, which is an external browser operation. Sibling tool 'browser_switch_tab' exists, so this may be a variant that focuses/activates a tab. Empty description lowers confidence.

From the tool's definition Tool name 'browser_focus_tab' and server context of browser automation via Chromium plugin; description is empty and uninformative.

Documented attack patterns abuse exactly the kind of access browser_focus_tab gives an agent:

HOW TO CONTROL BROWSER_FOCUS_TAB

PolicyLayer is an MCP gateway — it sits between your AI agents and Cdp Bridge, and nothing reaches the server without passing your rules. This is the rule we recommend for browser_focus_tab:

policy.json

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

browser_focus_tab 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.

Create a free account and register Cdp Bridge — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RATE-LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

More Cdp Bridge tools

Execute browser_execute_js Execute JavaScript in the browser and capture results plus DOM changes. Args: Execute browser_navigate Navigate the active tab to a URL. Args: url: The URL to navigate to. Execute browser_wait Wait until JavaScript condition returns a truthy value. Args: condition_js: J Execute browser_batch browser_batch Execute browser_switch_tab Switch the active MCP browser tab without changing the visible Chrome tab. Args: Read browser_get_tabs Get all open browser tabs with their IDs, URLs, and titles. Read browser_scan Get simplified HTML content of the active tab plus tab list. The HTML is optimized for LLM Read browser_screenshot Take a screenshot of the active tab (returns base64 PNG). Args: tab_id: Optio

All 9 Cdp Bridge tools →

Execute tools on other servers

Frida Game Hacking MCP remove_breakpoint Procmon request_elevation WireMCP capture_packets Pentest Ai run_probe

Go deeper

High-risk tools in Cdp Bridge → Every high-risk tool this server exposes, in one view.
All high-risk MCP tools → Every high-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

What does the browser_focus_tab tool do? +

browser_focus_tab. It is categorised as a Execute tool in the Cdp Bridge MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on browser_focus_tab? +

Register the Cdp Bridge MCP server in PolicyLayer and add a rule for browser_focus_tab: 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 Cdp Bridge. Nothing to install.

What risk level is browser_focus_tab? +

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

Can I rate-limit browser_focus_tab? +

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

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

browser_focus_tab is provided by the Cdp Bridge MCP server (unagi-cq/cdp-bridge-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Cdp Bridge tool call.

Deterministic rules across all 9 Cdp Bridge tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

GOVERN CDP BRIDGE →

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9 Cdp Bridge tools catalogued and risk-classified — across an index of 42,500+ MCP servers.

// WHAT BROWSER_FOCUS_TAB ON CDP BRIDGE DOES

// THE RISK

// HOW TO CONTROL BROWSER_FOCUS_TAB

// EXPLORE