`YandexAdditionalBot`

Yandex's Search with Yandex AI page says a Disallow for YandexAdditional or YandexAdditionalBot keeps that page out of Yandex AI answers. The example disallows one path under User-agent: YandexAdditionalBot, and the page says the change applies after a recrawl, typically 2–14 days. The robot list says these tokens help process robots.txt for that purpose, apply to pages the primary crawler has already indexed, do not make indexing requests, and do not take the general rules into account. https://yandex.com/support/webmaster/en/yandex-ai The robot list says an agreement between Yandex and the site owner can override some robots.txt restrictions. This check does not apply that agreement.

robots.txt token: YandexAdditionalBot
Operator: Yandex
Kind: search
robots.txt: disallow_opts_out_ignores_star. The vendor says disallowing this token opts that use out. This robot does not take the general User-agent: * rules into account.
HTTP user-agent: Mozilla/5.0 (compatible; YandexAdditionalBot/1.0; +http://yandex.com/bots) The robot list also prints the short names YandexAdditionalBot and YandexAdditionalBot/1.0 on this row. YandexAdditional is a different token on the same row.
IP list: None on the cited page. The robot list says the IP list is not disclosed.
Source: How to check that a robot belongs to Yandex. Retrieved 2026-10-18.

JSON

curl -s https://whosthatbot.com/v1/crawlers/yandexadditionalbot

Check this token

tools/call with name check_robots is the same check at POST /mcp. The pasted file disallows YandexAdditionalBot on /docs and allows *. The call does not fetch a host.

curl -s https://whosthatbot.com/mcp -H 'content-type: application/json' -H 'accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"check_robots","arguments":{"robots_txt":"User-agent: YandexAdditionalBot\nDisallow: /\n\nUser-agent: *\nAllow: /\n","path":"/docs","ids":["yandexadditionalbot"]}}}'

That call returns fetched_target false. This row is disallow via group YandexAdditionalBot, rule Disallow: /.