Clean-param is a Yandex extension with no equivalent elsewhere: it tells the robot which URL parameters do not change the page content, so that variants converge on one address and accumulated metrics transfer to it. That transfer is why Yandex recommends it over Disallow for parameterised URLs.
How it works
Given three addresses differing only by a tracking parameter:
/some_dir/get_book.pl?ref=site_1&book_id=123
/some_dir/get_book.pl?ref=site_2&book_id=123
/some_dir/get_book.pl?ref=site_3&book_id=123the directive
User-agent: Yandex
Clean-param: ref /some_dir/get_book.plcollapses them to /some_dir/get_book.pl?book_id=123, which is what appears in search if it exists on the site. Note that book_id is preserved — the parameter that does determine content stays.
Site-wide form
Omit the path and the rule applies everywhere:
User-agent: Yandex
Clean-param: utmWhy keeping it current matters
Yandex explains the cost of neglect precisely: a new parameter that does not affect content produces duplicate pages, and because there are many of them the robot crawls the site more slowly — so important changes take longer to appear in search. A marketing team introducing a new tracking parameter is therefore making a crawl-budget decision without knowing it.
Syntax reminders
Parameters are separated by &; the path prefix is separated from them by a space. Getting this wrong raises the “invalid Clean-param directive format” error in the analyser, which is one of the Yandex-specific errors a generic robots.txt checker will not report.
Where it interacts with the console
The GET parameter settings page does the same job through the interface. When the two disagree, the rule that prevents indexing wins — so a stale Clean-param line silently overrides anything set in the interface.
Как мы это применяем
We keep a Clean-param line under review as part of ongoing work rather than writing it once, because every new campaign parameter that goes unlisted quietly multiplies the crawlable URL count. Explaining that link to the marketing team — new tracking parameter, slower indexing of new products — is more effective than any technical argument, because it connects the two things they each care about.
Связанные услуги