Line-by-line source finder
Paste an AI response. We cite every line .
LM Arena does not summarize the text and hunt for a few generic references.
It reads the response in order, line by line, statement by statement, and
looks up supporting URLs for each piece of information.
Web search providers
API status
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Wikipedia
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Openalex
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Duckduckgo
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Serper
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Serpapi
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Factcheck
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How a line is treated
The original line is kept intact — never rewritten into a digest.
Only substantive factual lines are cited and fact-checked; filler and transitions are skipped.
Long factual lines are split into sentences so each claim is searched on its own.
Nearby lines from the full response are passed as context when searching and fact-checking.
Skipped lines still appear in the dossier as "No claim". Serper and SerpAPI modes can be changed with the toggles in the API status panel.
Inspection in progress
Dossier