{"abstract":"The body diagonal is used as the cube side.","category":"Solid geometry","checks":4,"contract":"Nonnegative integer dimensions; exact products and ordinary Python real division. Quantities named divided by pi or pi-squared deliberately omit that factor from the returned result. diagonal_squared>=0; derive the volume of a cube from the squared body diagonal. Exact operational definition: (diagonal_squared/3)**1.5","contract_signature":"diagonal_squared","evaluation_group":"model-66084b90cd4ec688","failed_approach":"The face-diagonal relation is used for a body diagonal.","family":"xn-cube-volume-from-body-diagonal-squared","id":"FA-5986","implementations":{"attempt":{"sha256":"49e0e1a0744efee434416e49bdfd93fae5d4bfec28842c31d746e5bfa765bdb4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(diagonal_squared):\n    return (diagonal_squared/2)**1.5\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: (3,)', solve(*(3,)), 1)\ncheck('fixture 2: (12,)', solve(*(12,)), 8)\ncheck('fixture 3: (27,)', solve(*(27,)), 27)\ncheck('fixture 4: (0,)', solve(*(0,)), 0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"75b76ab944ae86752a0dc65aea36e94485ce8d2043dbef8f15bea7a360c9254b","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(diagonal_squared):\n    return diagonal_squared**1.5\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: (3,)', solve(*(3,)), 1)\ncheck('fixture 2: (12,)', solve(*(12,)), 8)\ncheck('fixture 3: (27,)', solve(*(27,)), 27)\ncheck('fixture 4: (0,)', solve(*(0,)), 0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xn-cube-volume-from-body-diagonal-squared","generated_at":"2026-09-29T14:37:56.196279+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Small exact fixtures expose this error without platform timing, external services, or probabilistic observations. Solid geometry results depend on the stated convention.","root_cause":"The body diagonal is used as the cube side.","sha256":"ab8a2266258f958d36da2801bbdd5a57f27d2baa071ad69615fc65f2e1b0be96","title":"Cube volume from body diagonal squared · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":43.79,"exit_code":1,"observations":[{"actual":1.8371173070873836,"check":"fixture 1: (3,)","expected":1,"passed":false},{"actual":14.696938456699069,"check":"fixture 2: (12,)","expected":8,"passed":false},{"actual":49.60216729135936,"check":"fixture 3: (27,)","expected":27,"passed":false},{"actual":0.0,"check":"fixture 4: (0,)","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: (3,)\", \"actual\": 1.8371173070873836, \"expected\": 1, \"passed\": false}, {\"check\": \"fixture 2: (12,)\", \"actual\": 14.696938456699069, \"expected\": 8, \"passed\": false}, {\"check\": \"fixture 3: (27,)\", \"actual\": 49.60216729135936, \"expected\": 27, \"passed\": false}, {\"check\": \"fixture 4: (0,)\", \"actual\": 0.0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":45.697,"exit_code":1,"observations":[{"actual":5.196152422706632,"check":"fixture 1: (3,)","expected":1,"passed":false},{"actual":41.569219381653056,"check":"fixture 2: (12,)","expected":8,"passed":false},{"actual":140.29611541307906,"check":"fixture 3: (27,)","expected":27,"passed":false},{"actual":0.0,"check":"fixture 4: (0,)","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: (3,)\", \"actual\": 5.196152422706632, \"expected\": 1, \"passed\": false}, {\"check\": \"fixture 2: (12,)\", \"actual\": 41.569219381653056, \"expected\": 8, \"passed\": false}, {\"check\": \"fixture 3: (27,)\", \"actual\": 140.29611541307906, \"expected\": 27, \"passed\": false}, {\"check\": \"fixture 4: (0,)\", \"actual\": 0.0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}