clear_cache

THE RISK

Critical Risk

Why clear_cache needs a policy

Clearing a cache permanently deletes stored response data that cannot be recovered. While the blast radius is limited (only cached web responses are lost, not source data), the action is irreversible, placing it in the Destructive category. Severity is medium because it can cause performance degradation and force re-fetching of data, but does not affect primary data sources.

From the tool's definition 'Clear the response cache' — irreversibly removes cached data; 'Use when cached data may be stale' confirms the intent is to wipe stored cache entries

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

POLICY

How to control clear_cache

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 clear_cache:

policy.json

{
  "version": "1",
  "default": "deny",
  "hide": [
    "clear_cache"
  ]
}

clear_cache disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.

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.

RESTRICT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Web Scraper tools

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. Execute browser_wait_for Wait for selector state or a fixed delay on the active page.

All 62 Web Scraper tools →

Destructive tools on other servers

Android Forensics ADB MCP Server create_full_backup 0xarchive web3_revoke_key Frida Game Hacking MCP clear_scan cPanel MCP Server clear_spam_box

Go deeper

Critical-risk tools in Web Scraper → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-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.
Blast radius → How much damage one compromised or confused agent can do — and how to bound it.
Tool call approval → Approval gates on individual tool calls: auto-allow, prompt, or deny.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about clear_cache

What does the clear_cache tool do? +

Clear the response cache. Use when cached data may be stale. It is categorised as a Destructive tool in the Web Scraper MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.

How do I enforce a policy on clear_cache? +

Register the Web Scraper MCP server in PolicyLayer and add a rule for clear_cache: 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 clear_cache? +

clear_cache is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit clear_cache? +

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

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

clear_cache 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 →