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YandexAdditional (Yandex): what it is and how to allow or block it

Updated · checked against the operator's documentation on

YandexAdditional is Yandex's robots.txt agent for Search with Yandex AI responses; it makes no indexing requests. Verify it by reverse DNS; block it by name, as it skips User-agent: *. Its robots.txt token is YandexAdditional.

Facts

Operator
Yandex
Category
Special-purpose crawler
robots.txt token
YandexAdditional
Honors robots.txt?
Yes, when named (ignores *), per Yandex. Yandex marks it as not taking the general robots.txt rules into account and says such robots need directives that name them. Yandex lists two names, YandexAdditional and YandexAdditionalBot.
User-agent example
Mozilla/5.0 (compatible; YandexAdditional/1.0; +http://yandex.com/bots)
Official source
Yandex: Verifying Yandex robots
Compared with the source

What it is used for

Per Yandex, it helps process robots.txt to prevent page content from appearing in Search with Yandex AI responses. It applies to pages already indexed by the primary crawler and does not make indexing requests.

What happens if you block it

Per Yandex, a rule for it keeps page content out of Search with Yandex AI responses. It makes no indexing requests itself; the Yandex index is built by YandexBot.

Yandex documents a second form, Mozilla/5.0 (compatible; YandexAdditionalBot/1.0; +http://yandex.com/bots). Both contain YandexAdditional, which this page matches.

Is it really YandexAdditional?

Anyone can send YandexAdditional as a user agent, so a log line proves nothing by itself. The way to tell is the requesting IP address.

How to allow or block YandexAdditional

Add one of these groups to the robots.txt at the root of your domain. A group that names the bot overrides a general User-agent: * group.

Allow YandexAdditional
User-agent: YandexAdditional
Allow: /
Block YandexAdditional
User-agent: YandexAdditional
Disallow: /

Does your site allow YandexAdditional today? The checker evaluates your robots.txt for this and every other bot.Check my site

What we see on this site

No request identifying as YandexAdditional has been recorded since 19 Oct, so there is nothing to show yet. We never fill this in with estimates.

Counts come from this site's own server; they hold no IP addresses or URLs, and a user agent is only a claim. See the bot traffic data and the methodology.

Questions about YandexAdditional

What is YandexAdditional?

Yandex's robot that applies robots.txt rules to keep page content out of Search with Yandex AI responses. Per Yandex, it helps process robots.txt to prevent page content from appearing in Search with Yandex AI responses. It applies to pages already indexed by the primary crawler and does not make indexing requests.

Is YandexAdditional safe and legitimate?

The real YandexAdditional is a special-purpose crawler run by Yandex. A user-agent string is only a claim, though, so anyone can send it. Yandex documents a reverse lookup whose name ends in yandex.ru, yandex.net or yandex.com, followed by a forward lookup that must return the same address. It does not publish its robots' IP addresses.

Does YandexAdditional obey robots.txt?

Yes, when named (ignores *), per Yandex. Yandex marks it as not taking the general robots.txt rules into account and says such robots need directives that name them. Yandex lists two names, YandexAdditional and YandexAdditionalBot.

How do I block YandexAdditional?

Add a group to the robots.txt at the root of your domain: User-agent: YandexAdditional followed by Disallow: /. A group that names the bot overrides a general User-agent: * group.

Will blocking YandexAdditional hurt my Google rankings or AI visibility?

Per Yandex, it only decides whether page content appears in Search with Yandex AI responses. Indexing is done by YandexBot, which has its own token.

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