browser_accessibility_tree

THE RISK

Low Risk

Why browser_accessibility_tree needs a policy

This tool queries and retrieves accessibility metadata from a web page without side effects. It is a read-only operation that extracts structured data about page semantics and accessibility properties. While the tool operates within a browser automation context, the specific action is data retrieval, not navigation, interaction, or execution of arbitrary code.

From the tool's definition Tool returns a snapshot (read-only retrieval) of accessibility tree information via Playwright's accessibility API. Description uses 'Return' indicating data retrieval with no modification, creation, deletion, or code execution.

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

POLICY

How to control browser_accessibility_tree

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

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "browser_accessibility_tree": {}
  }
}

browser_accessibility_tree is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

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

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Web Scraper tools

Destructive clear_cache Clear the response cache. Use when cached data may be stale. Destructive clear_history Clear scraping history. Destructive clear_host_profile Delete one host profile record from the profile store. Destructive clear_session Clear a browser session (cookies, storage). Use for fresh starts. Execute cancel_job Cancel a running async job. Execute browser_evaluate Run a JavaScript expression on the current page and return the result. Execute browser_navigate Navigate the interactive browser to a URL. Execute browser_solve_challenge Explicitly trigger challenge detection and solving on the current page.

All 62 Web Scraper tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about browser_accessibility_tree

What does the browser_accessibility_tree tool do? +

Return a trimmed Playwright accessibility snapshot. It is categorised as a Read tool in the Web Scraper MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on browser_accessibility_tree? +

Register the Web Scraper MCP server in PolicyLayer and add a rule for browser_accessibility_tree: 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 Web Scraper. Nothing to install.

What risk level is browser_accessibility_tree? +

browser_accessibility_tree is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit browser_accessibility_tree? +

Yes. Add a rate_limit block to the browser_accessibility_tree 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_accessibility_tree completely? +

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

browser_accessibility_tree is provided by the Web Scraper MCP server (imyourboyroy/webscrapertoolkit). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Web Scraper tool call.

Start from Web Scraper, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →