The biggest AI crawlers — OpenAI's GPTBot, Anthropic's ClaudeBot, PerplexityBot — fetch a page's raw HTML and stop. They do not execute JavaScript. Whatever a site loads or renders after that first response is invisible to them. So Antileak measures a site the same way: one HTTP fetch of the homepage, no JavaScript executed, and everything we report is a statement about what that fetch returned.
robots.txt with the same group-precedence rules the crawlers use (a named group beats the wildcard group), and we report which AI crawlers are blocked, by name. We also obey it ourselves: our scanner announces itself as AntileakBot, and a site that disallows us is not scanned — see antileak.io/bot.LocalBusiness markup exists and which of the fields AI answers are built from — name, address, telephone, opening hours, geo, price range — actually carry a value. Empty markup is reported as what it is.<title>, meta description and H1, response time and page weight, and broken links among the homepage's own links (capped by a fixed request budget so we never hammer anyone's server).alt attribute. All of it read from the same homepage HTML above — no extra requests. An alt="" is not counted as missing: that is the correct way to mark an image decorative, and we are not going to tell anyone to break it.Sitemap: line in the robots.txt we already fetched. Only if there isn't one do we send a single HEAD /sitemap.xml. If the request budget has already run out, we report nothing rather than reporting an absence we didn't check.default, google, zmail, s1, selector1, selector2), so a negative result means we found no key at those selectors — not that none exists anywhere. No mail is sent to check any of this; DNS is public.It does not render the page in a browser, so it cannot say what appears after JavaScript runs — only what is present before. It does not cross-check business details against Google or directories, read certificate expiry dates, or inspect trackers and consent banners. Where a page of ours lists capabilities, unbuilt ones are labelled as not built; we don't charge for them or claim them.
The health score is a weighted 0–100 roll-up of the measured checks above — presence of structured data, crawler access, fundamentals, email authentication, and response behaviour. It exists to make one site comparable to itself over time. It is our scale, computed only from our own measurements, and a score is never published for a named business.
Site owners can block AntileakBot in robots.txt — we check before any request and honour it — or ask never to be scanned at services@antileak.io, which also removes any stored report for the domain.