DuckAssistBot
DuckDuckGo · Live retrieval · robots.txt token duckassistbot
2% of 30,177 measured domains disallow duckassistbot in robots.txt at the site root. Separately, and independently of robots.txt, 17.4% of 30,187 reachable domains refuse an AI crawler user agent at the network edge on two consecutive probes from different locations - a refusal the site's own robots.txt does not declare and its owner often has not chosen.
Measured 2026-10-06 by direct request to every domain in the corpus. Method: how this is measured. Reuse under CC BY 4.0 with attribution.
Cite as: Crawl Census, "DuckAssistBot blocking rate", measured 2026-10-06. https://crawlcensus.com/bot/duckassistbot
What it is definition
Crawls pages in real time for DuckDuckGo's cited AI-assisted answers; not used for model training.
DuckAssistBot is operated by DuckDuckGo and classified here as live retrieval. These agents fetch a single URL because a user asked about it. Disallowing one means the assistant answers from an older copy or from someone else's summary instead of the live page. Several are documented as not bound by robots.txt, because the request is user-initiated rather than a crawl.
Disallowing duckassistbot stops the fetch that happens when a user asks DuckDuckGo AI answers about one of your URLs. The answer still gets written, from an older copy or from a third party's description of the page, and you no longer control what it says.
- robots.txt token
- duckassistbot
- Operator
- DuckDuckGo
- Purpose
- Live retrieval
- Honors robots.txt
- yes
- Documentation
- https://duckduckgo.com/duckduckgo-help-pages/results/duckassistbot/
Identity on the wire exact string
DuckAssistBot/1.2; (+http://duckduckgo.com/duckassistbot.html)curl -A 'DuckAssistBot/1.2; (+http://duckduckgo.com/duckassistbot.html)' https://example.com/Replace the host with your own. A 403, a challenge page or an empty body means the edge is blocking the agent whatever robots.txt says.
How to allow it, how to block it robots.txt
User-agent: duckassistbot
Allow: /Absent any rule, the agent is already allowed, so this group only matters when your * group disallows something. Naming the agent replaces the * group for it entirely, so repeat here every disallow you still want to apply to it.
User-agent: duckassistbot
Disallow: /Disallowing duckassistbot stops the fetch that happens when a user asks DuckDuckGo AI answers about one of your URLs. The answer still gets written, from an older copy or from a third party's description of the page, and you no longer control what it says.
Sites that block it 60 shown
See every measured domain that blocks DuckAssistBot
This list is served from a cache rebuilt just now. It is discarded the moment a rescan records a policy change for this agent, so a site that has just changed its robots.txt will drop off it within one scan rather than waiting for the cache to expire.
Compare DuckDuckGo
DuckDuckGo runs no other agent in this registry.
Common questions answered
Does blocking DuckAssistBot remove me from DuckDuckGo AI answers?
Partly. DuckAssistBot fetches a page only when a user asks about it, so disallowing it does not delist you from DuckDuckGo AI answers. It does mean the answer is composed without your live page, from a stale copy or a third-party summary.
How do I verify DuckAssistBot requests are genuine?
DuckDuckGo lists the addresses its assistant crawler fetches from on the DuckAssistBot help page. Compare the source address against that list.
Check your own site free
See whether your robots.txt admits DuckAssistBot today, and whether your edge agrees with it.