DuckAssistBot
DuckDuckGo · reviewed 2026-11-05
About DuckAssistBot
Fetches pages to draft Duck.ai's AI-assisted answers.
Operates DuckDuckGo Search and Duck.ai; DuckAssistBot fetches pages to draft AI-assisted answers.
Usually means: A person asked an AI assistant a question, and the assistant fetched this URL to answer with fresh context or citations.
Identity
User agent
Crawlers are matched by token, not the full browser string. Providers may add version or product text around it.
robots.txt token
Use this token in a User-agent line to allow or block the crawler.
Block this token
User-agent: DuckAssistBot Disallow: /
A Disallow only stops crawlers that honor robots.txt. Classify the category before blocking; check the live file with the robots.txt checker.
Verify a hit
A matching user agent is not proof: any client can send the string. When the vendor publishes network data, compare the request against it before you trust the hit.
Match the user agent
Request UA contains DuckAssistBot.
Check reverse DNS
Hostname ends with duckduckgo.com.
Check the IP range
Fetch the endpoint below and compare the request IP.
Reverse-DNS suffixes
duckduckgo.comRange endpoints
A verified hit proves the network path; it does not prove what the crawler will do with the page.
DuckAssistBot: common questions
What is DuckAssistBot?
DuckAssistBot is a crawler from DuckDuckGo, filed under AI answers. Fetches pages to draft Duck.ai's AI-assisted answers. Requests advertise it in the User-Agent header as DuckAssistBot.
Does DuckAssistBot train AI models?
No. It fetches a page only when a person asks DuckDuckGo's assistant a question that needs live context.
How do I block DuckAssistBot in robots.txt?
Add a group with User-agent: DuckAssistBot and Disallow: / to robots.txt, then re-test the live file. robots.txt matches the token, not the full User-Agent string, and blocking this token does not block the vendor's other crawlers.
How do I verify a DuckAssistBot hit?
Match the user agent, then compare the request IP with the ranges or endpoints listed on this page and check that the hostname ends with duckduckgo.com. A matching user agent alone is not proof — any client can send the string.
Testing a block? Run the live file through the robots.txt tester or check the whole AI crawler access group.
See when DuckAssistBot hits your site
Page scripts never see AI crawlers because they do not run JavaScript. Install the server probe and each hit lands in the Crawlers block with its path and status.