{"query": "Luhn(4532 0151 1283 0366) is valid · ISBN-13 978-0-306-40615", "count": 4, "results": [{"id": "card_v_50597b7a3831", "title": "Luhn(4532 0151 1283 0366) is valid · ISBN-13 978-0-306-40615-7 is valid", "shelf": "document_validation", "surface": "secular", "snippet": "Verdict: HOLDS.\n• doc_validation.luhn: Luhn '4532015112830366' valid=True (matches claim)\n• doc_validation.isbn13: ISBN-13 '9780306406157' valid=True (matches claim)\nSealed and independently re-checka", "authority_tier": "engine", "source": "Verified by the engine — document_validation", "generated": false}, {"id": "card_domchk_document_validation_claimed_luhn_valid", "title": "Document Validation: luhn valid", "shelf": "document_validation", "surface": "secular", "snippet": "A worked check in document validation: luhn valid.\n\nGIVEN\n  luhn_number = 4532015112830366\n\nCLAIMED\n  claimed_luhn_valid = True\n\nTHE ENGINE'S VERDICT\n  doc_validation.luhn: CONFIRMED — Luhn '453201511", "authority_tier": "reference", "source": "The verifier's own documented relation, and a run this engine performed against it (deterministic; re-runnable with tools/domain_goldens.py)", "generated": false}, {"id": "card_works_luhn", "title": "The check digit that catches a mistyped number", "shelf": "the-works", "surface": "secular", "snippet": "The Luhn and ISBN algorithms embed a check digit so a single wrong digit is caught before it becomes a wrong order or a wrong book. Two standards, both verified.  Worked & sealed by the engine — Luhn(", "authority_tier": "verified", "source": "The Works — worked & sealed", "generated": false}, {"id": "card_src_pron_luhn", "title": "luhn", "shelf": "pronunciation", "surface": "secular", "snippet": "", "authority_tier": "", "source": "", "generated": false}]}