What is DuckAssistBot's user-agent string?

DuckAssistBot/1.2; (+http://duckduckgo.com/duckassistbot.html) (vendor-documented on the DuckDuckGo help pages)

DuckAssistBot

Q: What is DuckAssistBot?

DuckAssistBot is DuckDuckGo's search-index crawler — it crawls proactively to build the search index the assistant cites in answers. Allowing it is how your pages become citable.

DuckDuckGo · Search-index crawler · Updated 2026-07-19

DuckAssistBot is DuckDuckGo’s search-index crawler — it crawls proactively to build the search index the assistant cites in answers. Allowing it is how your pages become citable.

User-agent string

DuckAssistBot/1.2; (+http://duckduckgo.com/duckassistbot.html)

Source: vendor-documented on the DuckDuckGo help pages.

Does DuckAssistBot respect robots.txt?

Respects robots.txt — DuckDuckGo states a new disallow takes effect within 72 hours and that opting out “does not impact organic search rankings.” It also states: “This data is not used in any way to train AI models.”

Allow or block DuckAssistBot

# Allow (recommended if you want DuckAssistBot traffic)
User-agent: DuckAssistBot
Allow: /

# Block
User-agent: DuckAssistBot
Disallow: /

Verifying it’s really DuckAssistBot

DuckDuckGo publishes the full IP list at duckduckgo.com/duckassistbot.json. The addresses are Azure ranges, so reverse DNS will not show a DuckDuckGo domain — match the list instead. User-agent strings can be spoofed by anyone — identity claims are only trustworthy when the source IP matches the operator’s published ranges.

Fetch the published ranges and check a suspect IP against them:

curl -s https://duckduckgo.com/duckassistbot.json

What site owners should know

Crawls pages in real time for DuckDuckGo’s AI-assisted answers, which prominently cite their sources. Distinct from DuckDuckBot, the regular search-index crawler.

Scan your site to see how your robots.txt, content negotiation, and discovery files treat AI agents — including whether you’re blocking agents you meant to allow. Background: the robots.txt guide, how AI agents browse, and agent readiness.

All AI agent user-agents

ClaudeBot · Claude-User · Claude-SearchBot · GPTBot · OAI-SearchBot · ChatGPT-User · PerplexityBot · Perplexity-User · Google-Extended · Google-Agent · Google-CloudVertexBot · Meta-ExternalAgent · Meta-ExternalFetcher · MistralAI-User · Applebot · Applebot-Extended · Amazonbot · bingbot · DuckAssistBot · CCBot · Bytespider