extract_data

THE RISK

Low Risk

Why extract_data needs a policy

This tool queries and retrieves information from a web page without creating, modifying, or deleting any data. It has no destructive, financial, or code-execution implications. The operation is passive data retrieval, fitting the Read category definition (retrieves or queries data; no side effects). Severity is low because misuse would only expose publicly accessible web content already visible to the AI.

From the tool's definition Tool description states it 'Extract[s] structured data (JSON) from a web page URL' — a retrieval operation with no modification or side effects. The verb 'extract' and context of parsing web page content indicate read-only data extraction.

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

POLICY

How to control extract_data

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

policy.json

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

extract_data 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 ReviewWebsite MCP Server — 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 ReviewWebsite MCP Server tools

Execute html_to_screenshot Convert HTML content to a screenshot image using ReviewWeb.site API. Renders raw HTML s Read extract_data_multiple Extract structured data (JSON) from multiple web page URLs using AI via ReviewWeb.site API Read extract_links Extract all links from a HTML content of web page URL using ReviewWeb.site API. Read scrape_url Scrape a URL and return HTML content using ReviewWeb.site API. Read seo_backlinks Get backlinks for a domain using ReviewWeb.site API. Read seo_keyword_difficulty Get keyword difficulty for a keyword using ReviewWeb.site API. Read seo_keyword_ideas Get keyword ideas for a keyword using ReviewWeb.site API. Read seo_traffic Check traffic for a domain or URL using ReviewWeb.site API.

All 16 ReviewWebsite MCP Server 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 extract_data

What does the extract_data tool do? +

Extract structured data (JSON) from a web page URL using AI via ReviewWeb.site API. It is categorised as a Read tool in the ReviewWebsite MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on extract_data? +

Register the ReviewWebsite MCP Server MCP server in PolicyLayer and add a rule for extract_data: 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 ReviewWebsite MCP Server. Nothing to install.

What risk level is extract_data? +

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

Can I rate-limit extract_data? +

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

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

extract_data is provided by the ReviewWebsite MCP Server MCP server (mrgoonie/reviewwebsite-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every ReviewWebsite MCP Server tool call.

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

CHECK YOUR STACK →