foureff
recommended: observe4F operates a web crawler on behalf of its users. It continuously monitors sites for broken links and failing assets.
How to identify it
User-agent contains any of:
4f.at/crawler
How to verify it's genuine
foureff signs its requests with Web Bot Auth. Botscope verifies the HTTP Message Signature against the operator's published key directory — a forged signature is flagged instantly. View the key directory ↗
robots.txt
Well-behaved crawlers honor robots.txt. To control foureff:
Allow full access
User-agent: 4f.at/crawler
Allow: /Block entirely
User-agent: 4f.at/crawler
Disallow: /
Grey-area scrapers ignore robots.txt. Botscope enforces your policy at the edge or origin regardless —
see how →
References
See foureff on your own site
Botscope shows every bot and AI agent hitting your site — and lets you allow, challenge, or block each one. Observe first, enforce when you're ready.
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