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Also grab the title and publisher while you're at it."},{"title":"Retrieve license info before reproducing a figure","prompt":"I want to reuse a figure from the paper DOI 10.1038/nature12373 — can you look up its license details and tell me if there are any restrictions on reuse?"}],"resultDescription":"A JSON object containing the DOI, canonical URL, article type, publication year, title, list of authors (given and family names), citation count, publisher name, license details (URL, start date, content version), and source provenance metadata including when the record was fetched and its expiry.","failureModes":["Invalid or malformed DOI format (must match pattern ^10\\.[0-9]{4,9}/\\S+$) returns a validation error","DOI not found in Crossref registry returns a 404 or empty result","Crossref API upstream unavailability causes a timeout or 503","Payment not completed (x402 payment required) results in a 402 response before data is returned","Rate limit or quota exhaustion on free tier blocks requests"],"whenToPreferThis":"Use this endpoint when you need structured, evidence-backed bibliographic metadata for a known DOI — especially when you need citation counts, license terms, author lists, or publisher details from Crossref specifically. 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