Anti-hallucination checker for legal references - verify...
Anti-hallucination checker for legal references — verify that cited cases, US Code sections, and CFR regulations in a passage actually EXIST, and (deterministically) that an attributed QUOTE actually appears in the cited opinion. POST { text } to scan a brief/passage: every case citation (via CourtListener), 'N U.S.C. § X', and 'N C.F.R. § X' is checked for existence with canonical metadata + a source URL, or flagged unverified. POST { quotes: [{ citation, quote }] } to verify specific quotations: each citation is resolved and its opinion full text is checked for the quote (ellipsis-aware), returning quote.present true/false. Pass both. Returns per-reference results + a summary (verified/unverified, quotesPresent/quotesMissing). Catches fabricated cases AND fabricated quotations — the LLM legal-output failure mode that gets attorneys sanctioned. Note: this checks existence + quote presence (facts), NOT whether a case legally supports a proposition. Sources: CourtListener (Free Law Project), US OLRC, eCFR (public domain).
Request
- Base URL: https://2s.io
- URL: https://2s.io/api/law/citation-check
- Auth: API key in header PAYMENT-SIGNATURE
Query parameters
Try before you buy. Set to 1 for one free real call per endpoint per hour — no wallet or payment needed — to verify the endpoint before paying. Equivalent to sending the "X-2s-Trial: 1" request header. Listed only on operations that offer a trial; the others always answer 402.
Request body
Response
Changes
No recorded changes to this operation across all 1 revision of this API.