yacybot
Operated by YaCy Community
Quick Facts
- User-Agent:
- yacybot
- Category:
- Data Scrapers
- Operator:
- YaCy Community
- Safety:
- Safe
- Blocking Impact:
- Low - No SEO ranking impact
- SEO Impact Score:
- 2/10
- Official docs:
- yacy.net
Confirmed by the operator
YaCy Community names yacybot on its own documentation page, linked above. The token, purpose and robots.txt behaviour on this profile come from that page, re-checked on October 19, 2026.
What is yacybot?
The bot user-agent for YaCy crawler nodes.
The bot user-agent for YaCy crawler nodes.
yacybot is a data aggregation crawler. Unlike search bots or AI crawlers, its purpose is typically to collect content for private datasets, price monitoring, or research. Blocking yacybot via robots.txt or at the server level has NO negative SEO impact. If you see excessive crawl volume from this bot in your logs, a hard block is recommended.
What happens if you block yacybot?
How to block yacybot with robots.txt
<code>User-agent: yacybot</code> - Matching is case-insensitive. Robots.txt is fetched from the root of each subdomain separately.
Is yacybot safe to allow?
yacybot is verifiable via reverse-DNS lookup on the crawling IP addresses. You can safely allow it unless you have a specific reason to block (e.g., AI training opt-out or SEO tool visibility).What does yacybot do?
Understanding yacybot's purpose helps you decide whether to allow or block it.
- Extracts content, prices, or data from websites
- May be used for competitive intelligence
- Often operates without explicit permission
- Can increase server load and bandwidth usage
- May violate terms of service or copyright
yacybot in context
yacybot is a retrieval crawler that feeds AI search answers operated by YaCy Community. In plain terms, it builds a search or answer index. Our database files it under data scrapers and ranks it Tier 6, the lowest priority: scrapers and tools that offer most sites little or nothing. 37 of the 39 data scrapers in our database share this tier.
Its safety rating is safe and its blocking impact is low. So the decision about yacybot rests on what you want from YaCy Community, not on its behaviour. How we rate safety and impact.
How site owners treat yacybot
Our robots.txt study of the Tranco top 10,000 did not track yacybot as a named token, so we do not publish an adoption figure for it. If you run a large site, your own logs are the best evidence of how often it visits.
Does it follow robots.txt?
yacybot's operator does not clearly document how it treats robots.txt. Write the yacybot rule anyway, then confirm in your logs that its requests stop.
YaCy Community crawlers and close alternatives
yacybot is one of 2 YaCy Community crawlers in our database. A User-agent: yacybot group controls yacybot only; the other YaCy Community tokens below need their own lines.
yacybot: this crawler (Tier 6)yacy: yacy, builds a search or answer index (Tier 6)
To give yacybot the same answer as its siblings, stack User-agent: yacybot with their lines above one set of rules; to treat yacybot differently, give it its own group.
No other crawler in our data scrapers category has exactly the same purpose, which makes yacybot an unusual case: decide about it on its own merits.
We first recorded yacybot on March 17, 2026. YaCy Community documents it on yacy.net, and we recheck that page before each release.
Which rule yacybot actually follows
yacybot reads exactly one group in robots.txt, the most specific one that names yacybot, and never combines rules across groups. This short file shows the trap:
User-agent: *
Disallow: /private/
User-agent: yacybot
Disallow: /drafts/
- Find the group. yacybot looks for a group naming
yacybot. One exists, so it ignoresUser-agent: *completely. - Apply only that group. It is refused
/drafts/and nothing else. - The surprise.
/private/is open to yacybot, because that rule lives in the*group it no longer reads. To keep it out of both, repeatDisallow: /private/inside its own group.
Test yourself: does a rule under User-agent: * apply to yacybot if the file also has a User-agent: yacybot group?
No. Once a group names it, yacybot reads only that group. Put every rule you want it to follow inside its own group.
Test yourself: will blocking yacybot remove your pages from AI answers?
Often, yes. yacybot is a retrieval crawler that feeds AI search answers, so pages it cannot fetch can drop out of the answers or results it supports.
Test yourself: is User-agent: yacybot the same as User-agent: yacybot?
Yes. RFC 9309 makes user-agent matching case-insensitive. Paths are a different story: Disallow: /Blog/ does not block /blog/.
Should you allow yacybot? Decide by situation
| If you are... | Recommended setting |
|---|---|
| You publish content and want AI answers to cite it | Allow it. yacybot fetches pages for answers, so blocking it can remove you from them. |
| You license content and want to stop AI training | Blocking it does not stop training, because yacybot is a retrieval crawler that feeds AI search answers. Block the operator's training crawler instead. |
| You run an online shop | Allow it on product and category pages, which are the pages shoppers ask assistants about. |
| Your server is under load from bots | Rate-limit before blocking. It is rated safe in our database. |
Check yacybot on your own site
- Open
/robots.txton your domain and search foryacybot. If it is not named, it followsUser-agent: *. - List the
Disallowlines in the group yacybot follows and test your key URLs against them; the longest match wins, andAllowwins a tie. - Look beyond the file. A firewall or bot manager can refuse yacybot even when robots.txt allows it, and that never shows in the file.
- Run our live AI crawler test to see how yacybot and every other crawler we track are treated in one pass, including firewall refusals.
Common mistakes with yacybot
The errors we see most often with yacybot in the files and firewalls we test:
- Blocking yacybot while trying to stop AI training. Retrieval crawlers fetch pages so answers can cite them; blocking it can remove you from those answers without affecting training.
- Letting a firewall or bot-fight mode refuse yacybot while robots.txt allows it. The file looks right, but the crawler still gets a 403 or a challenge page.
- Forgetting that once a
User-agent: yacybotgroup exists, yacybot ignores every rule underUser-agent: *.
All three hide inside a file that looks correct, so check yacybot from outside after every change.
Spotting yacybot in your logs
robots.txt says what yacybot may do; your access logs show what it actually did.
Count requests
On a server with standard Nginx or Apache logs, this counts matching requests per day (adjust the log path for your host):
grep -iE "yacybot" /var/log/nginx/access.log \
| awk '{print $4}' | cut -d: -f1 | sort | uniq -c
And this shows which paths it requested most, which is the quickest way to see whether your Disallow lines are being respected:
grep -iE "yacybot" /var/log/nginx/access.log \
| awk '{print $7}' | sort | uniq -c | sort -rn | head -20
Check the requests are genuine
Anyone can send the yacybot user-agent, so confirm the source before acting on a match:
yacybot: we hold no published IP list, so use reverse DNS where the operator documents a hostname and treat an unverifiable yacybot request with caution.
Frequently Asked Questions
What is the official user-agent string for yacybot?
yacybot. This is the exact string you must use in robots.txt, Nginx, Apache, or Cloudflare firewall rules to target this bot. User-agent matching in robots.txt is case-insensitive, but the string must be spelled correctly. You can verify that a request genuinely comes from yacybot by performing a reverse-DNS lookup on the source IP - legitimate bots resolve back to their operator's domain.Is yacybot safe?
yacybot is verifiable via reverse-DNS lookup on the crawling IP addresses. You can safely allow it unless you have a specific reason to block (e.g., AI training opt-out or SEO tool visibility).Will blocking yacybot hurt my SEO?
How do I block yacybot in robots.txt?
/robots.txt file:User-agent: yacybot Disallow: /
This instructs yacybot not to crawl any path on your site. The Disallow: / directive covers the entire domain including subfolders. To only block specific sections, replace / with the path (e.g.,
Disallow: /blog/). Note: robots.txt is publicly readable - any bot or human can inspect it at yourdomain.com/robots.txt.Does yacybot respect robots.txt?
How do I verify if yacybot is crawling my site?
yacybot (case-insensitive grep: grep -i "yacybot" /var/log/nginx/access.log). You can also check Google Search Console → Coverage → Crawl Stats for Googlebot variants. For yacybot specifically, filter by user-agent in your log analysis tool (GoAccess, AWStats, etc.).What is the crawl frequency of yacybot?
User-agent: yacybot Crawl-delay: 10(10 second delay between requests).
Can I block yacybot from specific pages only?
Disallow: / you can restrict yacybot to specific paths:User-agent: yacybot Disallow: /private/ Disallow: /staging/ Allow: /
This allows yacybot everywhere except the listed paths. Path matching in robots.txt uses prefix matching -
Disallow: /private/ blocks /private/page.html but NOT /public/private/.Is yacybot causing high server load?
1. Add
Crawl-delay: 30 below the User-agent directive in robots.txt.2. Rate-limit the user-agent via Nginx's
limit_req_zone or Apache's mod_ratelimit.3. Block it outright at Cloudflare WAF with rule:
http.user_agent contains "yacybot".4. Use fail2ban to auto-block IPs exceeding request thresholds.