YandexAdditional user agent
Operated by Yandex
YandexAdditional is the Yandex robot that collects content for YandexGPT-generated answers and summaries.
The YandexAdditional bot at a glance
- YandexAdditional is operated by Yandex and collects public web pages that may be used to train AI models, and indexes web pages so an AI search product can show and cite them in answers.
- The robots.txt token for YandexAdditional is YandexAdditional.
- Blocking an AI training crawler has no effect on Google or Bing rankings.
- YandexAdditional robots.txt support: Yes.
- Recommendation for Generative Engine Optimization (GEO): Your choice.
What is YandexAdditional?
YandexAdditional and YandexAdditionalBot fetch pages so YandexGPT can generate quick answers and summaries in Yandex products.
Blocking them stops that use without removing pages from Yandex Search.
Should you block YandexAdditional?
Blocking YandexAdditional is a business decision: it protects your content but can lower how well AI products know your brand.
| Effect on search rankings | Blocking an AI training crawler has no effect on Google or Bing rankings. |
|---|---|
| Effect on AI visibility | Blocking keeps your future pages out of that company's training data, so its models may know less about your brand over time. It does not remove you from that company's AI search, which uses a separate bot. |
| Follows robots.txt | Yes |
| Recommendation | Your choice |
How to block or allow YandexAdditional
Put the robots.txt rule in the file at the root of every domain and subdomain, for example https://example.com/robots.txt. The token YandexAdditional is matched case-insensitively.
robots.txt: block
# Block YandexAdditional
User-agent: YandexAdditional
Disallow: /robots.txt: allow
# Allow YandexAdditional
User-agent: YandexAdditional
Allow: /robots.txt: partial
# Keep YandexAdditional out of private areas only
User-agent: YandexAdditional
Disallow: /wp-admin/
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Allow: /Nginx
# Nginx: return 403 to YandexAdditional
if ($http_user_agent ~* "(YandexAdditional)") {
return 403;
}Apache
# Apache .htaccess: return 403 to YandexAdditional
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} (YandexAdditional) [NC]
RewriteRule .* - [F,L]Cloudflare WAF
# Cloudflare > Security > WAF > Custom rule, action: Block
(http.user_agent contains "YandexAdditional")How to verify real YandexAdditional traffic
Reverse DNS check: look up the request IP, confirm the hostname ends in yandex.ru, yandex.net, yandex.com, then look up that hostname and confirm it returns the same IP.
# 1. Reverse lookup: the hostname must end in yandex.ru, yandex.net, yandex.com
host REQUEST_IP
# 2. Forward lookup: must return the same REQUEST_IP
host HOSTNAME_FROM_STEP_1How to find YandexAdditional in your server logs
Search the web server access log for the token. The command below counts YandexAdditional requests per URL on Nginx or Apache.
grep -i "YandexAdditional" access.log | awk '{print $7}' | sort | uniq -c | sort -rn | head -20For a full report per AI bot, upload the log to the AI Log File Analyzer, a free tool by Justin Hà.
YandexAdditional user agent string
The full user agent Yandex publishes for YandexAdditional. Version numbers such as Chrome/W.X.Y.Z change over time, so match the token, not the whole string.
Mozilla/5.0 (compatible; YandexAdditional/1.0; +http://yandex.com/bots)Mozilla/5.0 (compatible; YandexAdditionalBot/1.0; +http://yandex.com/bots)YandexAdditional FAQ
YandexAdditional identifies itself with the robots.txt token "YandexAdditional". A typical request header reads: Mozilla/5.0 (compatible; YandexAdditional/1.0; +http://yandex.com/bots)
Yes. Yandex states that YandexAdditional follows robots.txt rules written for the "YandexAdditional" token.
Blocking an AI training crawler has no effect on Google or Bing rankings. Blocking keeps your future pages out of that company's training data, so its models may know less about your brand over time. It does not remove you from that company's AI search, which uses a separate bot.
Add two lines to the robots.txt file at the root of each domain and subdomain: "User-agent: YandexAdditional" followed by "Disallow: /". The token is case-insensitive. Changes can take up to 24 hours to be picked up.
Yes. Run a reverse DNS lookup on the request IP; a real YandexAdditional request resolves to yandex.ru, yandex.net, yandex.com, and a forward lookup of that hostname returns the same IP.
Search your server access log for "YandexAdditional", for example with: grep -i "YandexAdditional" access.log. The AI Log File Analyzer by Justin Hà counts visits per AI bot from an uploaded log file.
Sources: Yandex crawler documentation. Last reviewed by Justin Hà.
See which of these bots actually reach your website
The AI Log File Analyzer by Justin Hà counts visits from GPTBot, ClaudeBot, PerplexityBot and other AI crawlers in your server log, for free. The GEO Technical Package sets up robots.txt, llms.txt and crawler access for AI search.
