Requests with the user agent CrawlSentry/1.0 come from CrawlSentry, a service site owners use to monitor their own pages for accidental SEO configuration changes (noindex, canonical, robots.txt, title, redirects).
Each monitored URL is fetched at most about once per hour, plus /robots.txt for its host, and once a day the XML sitemap(s) listed there (to alert if a sitemap disappears). We read only the HTML <head> and do not follow links or crawl.
When someone runs our free AI visibility check on a URL, we fetch that one page in full, /llms.txt, and send a few requests whose user agent names an AI crawler (e.g. OAI-SearchBot) followed by CrawlSentry-AccessTest/1.0, to see whether a CDN or firewall treats AI crawlers differently. These are one-off requests, cached for 5 minutes.
Questions or opt-out: support@crawlsentry.com.