YiyanBot user agent
Operated by Baidu
YiyanBot is a Baidu fetcher reported as reading web pages for the Wenxin Yiyan (ERNIE Bot) assistant.
The YiyanBot bot at a glance
- YiyanBot is operated by Baidu and fetches a page when a person asks an AI assistant about it or shares its link.
- The robots.txt token for YiyanBot is YiyanBot.
- Blocking an AI assistant fetcher has no effect on search rankings.
- YiyanBot robots.txt support: Not documented.
- Recommendation for Generative Engine Optimization (GEO): Your choice.
What is YiyanBot?
YiyanBot fetches pages used in answers from Baidu’s ERNIE-based assistant.
It is separate from Baiduspider, which indexes pages for Baidu Search.
Should you block YiyanBot?
Blocking YiyanBot 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 assistant fetcher has no effect on search rankings. |
|---|---|
| Effect on AI visibility | Blocking stops the assistant from reading your page when a user asks about it or pastes your link, so its answer falls back to other sources. |
| Follows robots.txt | Not documented |
| Recommendation | Your choice |
How to block or allow YiyanBot
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 YiyanBot is matched case-insensitively. robots.txt alone may not stop YiyanBot, so add the Nginx, Apache or Cloudflare rule as well.
robots.txt: block
# Block YiyanBot
User-agent: YiyanBot
Disallow: /robots.txt: allow
# Allow YiyanBot
User-agent: YiyanBot
Allow: /robots.txt: partial
# Keep YiyanBot out of private areas only
User-agent: YiyanBot
Disallow: /wp-admin/
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Allow: /Nginx
# Nginx: return 403 to YiyanBot
if ($http_user_agent ~* "(YiyanBot)") {
return 403;
}Apache
# Apache .htaccess: return 403 to YiyanBot
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} (YiyanBot) [NC]
RewriteRule .* - [F,L]Cloudflare WAF
# Cloudflare > Security > WAF > Custom rule, action: Block
(http.user_agent contains "YiyanBot")How to verify real YiyanBot traffic
Baidu publishes no IP list or reverse DNS pattern for YiyanBot, so the user agent cannot be verified. Anyone can send the same string. Rate-limit unusual volume instead of trusting the name.
How to find YiyanBot in your server logs
Search the web server access log for the token. The command below counts YiyanBot requests per URL on Nginx or Apache.
grep -i "YiyanBot" 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.
YiyanBot FAQ
YiyanBot uses the robots.txt token "YiyanBot". Baidu does not publish a full user-agent string, so match the token inside the User-Agent header.
Baidu has not documented how YiyanBot treats robots.txt. Add a robots.txt rule and back it with a server rule if the traffic matters to you.
Blocking an AI assistant fetcher has no effect on search rankings. Blocking stops the assistant from reading your page when a user asks about it or pastes your link, so its answer falls back to other sources.
Add two lines to the robots.txt file at the root of each domain and subdomain: "User-agent: YiyanBot" followed by "Disallow: /". The token is case-insensitive. Changes can take up to 24 hours to be picked up.
Not reliably. Baidu publishes no IP list or reverse DNS pattern for YiyanBot, so anyone can send the same user agent. Rate-limit unusual volume instead of trusting the name.
Search your server access log for "YiyanBot", for example with: grep -i "YiyanBot" access.log. The AI Log File Analyzer by Justin Hà counts visits per AI bot from an uploaded log file.
Sources: Public bot registry. 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.
