{"abstract":"A sample on a shared boundary is counted in both adjacent windows.","category":"Data systems","checks":3,"contract":"Use half-open intervals consistently across adjacent windows.","contract_signature":"windows, t","evaluation_group":"model-21d4faf29b891e6b","failed_approach":"Making both ends exclusive drops samples at window starts.","family":"window-boundary","id":"FA-036","implementations":{"attempt":{"sha256":"cc4a5e9cd2a3aa6a3b1223e024c4d8250a7b07c038dd4b579313b6fbd90eb539","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(windows, t):\n    return sum(start < t < end for start, end in windows)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nwindows = [[0, N], [N, 2*N]]\ncheck('shared boundary', solve(windows, N), 1)\ncheck('first boundary', solve(windows, 0), 1)\ncheck('outside final boundary', solve(windows, 2*N), 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":"283ae8306240a405ef37f7797d43d6eca20467b8a3f5c85a6e0cd551545f09af","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(windows, t):\n    return sum(start <= t <= end for start, end in windows)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nwindows = [[0, N], [N, 2*N]]\ncheck('shared boundary', solve(windows, N), 1)\ncheck('first boundary', solve(windows, 0), 1)\ncheck('outside final boundary', solve(windows, 2*N), 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":"window-boundary","generated_at":"2026-09-29T14:36:49.871757+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A compact reasoning and repair task with executable evidence.","root_cause":"Both ends of every interval are inclusive.","sha256":"bc275c6b72b276e92d94f77d1be2ce11aec0ee5660fef8fe2301750b69770729","title":"Adjacent windows count a boundary twice · 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":30.297,"exit_code":1,"observations":[{"actual":0,"check":"shared boundary","expected":1,"passed":false},{"actual":0,"check":"first boundary","expected":1,"passed":false},{"actual":0,"check":"outside final boundary","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"shared boundary\", \"actual\": 0, \"expected\": 1, \"passed\": false}, {\"check\": \"first boundary\", \"actual\": 0, \"expected\": 1, \"passed\": false}, {\"check\": \"outside final boundary\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":35.61,"exit_code":1,"observations":[{"actual":2,"check":"shared boundary","expected":1,"passed":false},{"actual":1,"check":"first boundary","expected":1,"passed":true},{"actual":1,"check":"outside final boundary","expected":0,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"shared boundary\", \"actual\": 2, \"expected\": 1, \"passed\": false}, {\"check\": \"first boundary\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"outside final boundary\", \"actual\": 1, \"expected\": 0, \"passed\": false}], \"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."}}