{"abstract":"Pair orientation checks total balance but misses streak bans.","category":"Tournament pairing rules","checks":6,"contract":"Synthetic model: Return whether appending W or B avoids a run of three identical colors. Only the final two historical colors matter; total balance is not a rule in this model.","evaluation_group":"model-85ff337a96732659","failed_approach":"Banning any repeated color overrestricts the permitted second consecutive assignment.","family":"z-tournament_pairing-color-streak","id":"FA-12831","implementations":{"attempt":{"sha256":"6d4ed8abfbd5f1a8ad7b5de31857b78014868b39ca1d4c1d58ea610dac696129","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(history, next_color):\n    return not (history and history[-1]==next_color)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('third same after balance', solve(\"B\"*N+\"WW\", \"W\"), False)\ncheck('second allowed', solve(\"W\", \"W\"), True)\ncheck('empty', solve(\"\", \"B\"), True)\ncheck('switch', solve(\"WW\", \"B\"), True)\ncheck('black third', solve(\"W\"*N+\"BB\", \"B\"), False)\ncheck('alternating', solve(\"WB\"*N, \"W\"), True)\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":"148c6c4b135e3aaee17dee41282bb2774e6cf801f63fe2528745948ecdf5b1ac","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(history, next_color):\n    return abs(history.count('W')-history.count('B')+(1 if next_color=='W' else -1))<=2\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('third same after balance', solve(\"B\"*N+\"WW\", \"W\"), False)\ncheck('second allowed', solve(\"W\", \"W\"), True)\ncheck('empty', solve(\"\", \"B\"), True)\ncheck('switch', solve(\"WW\", \"B\"), True)\ncheck('black third', solve(\"W\"*N+\"BB\", \"B\"), False)\ncheck('alternating', solve(\"WB\"*N, \"W\"), True)\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"},"fixed":{"sha256":"8fba1e515cd478c3ade6fbf8bc09fa0c950a0ce53b6687d6f33cc7d6b4225403","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(history, next_color):\n    return not (len(history)>=2 and history[-2:]==next_color*2)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('third same after balance', solve(\"B\"*N+\"WW\", \"W\"), False)\ncheck('second allowed', solve(\"W\", \"W\"), True)\ncheck('empty', solve(\"\", \"B\"), True)\ncheck('switch', solve(\"WW\", \"B\"), True)\ncheck('black third', solve(\"W\"*N+\"BB\", \"B\"), False)\ncheck('alternating', solve(\"WB\"*N, \"W\"), True)\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":"Controlled synthetic policy; does not implement an entire tournament system. 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":"z-tournament_pairing-color-streak","generated_at":"2026-09-29T14:39:00.611340+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Makes the stated pairing or standings policy executable without assuming any real federation rulebook.","repair":"Return whether appending W or B avoids a run of three identical colors. Only the final two historical colors matter; total balance is not a rule in this model.","root_cause":"A cumulative balance surrogate does not enforce the consecutive-color constraint.","sha256":"cd360ae7f734d7e982e1043c75413dbe36a8dda5fd39a1dfe492538d7a36834d","title":"Pair orientation checks total balance but misses streak bans · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":43.144,"exit_code":1,"observations":[{"actual":false,"check":"third same after balance","expected":false,"passed":true},{"actual":false,"check":"second allowed","expected":true,"passed":false},{"actual":true,"check":"empty","expected":true,"passed":true},{"actual":true,"check":"switch","expected":true,"passed":true},{"actual":false,"check":"black third","expected":false,"passed":true},{"actual":true,"check":"alternating","expected":true,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"third same after balance\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"second allowed\", \"actual\": false, \"expected\": true, \"passed\": false}, {\"check\": \"empty\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"switch\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"black third\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"alternating\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.439,"exit_code":1,"observations":[{"actual":true,"check":"third same after balance","expected":false,"passed":false},{"actual":true,"check":"second allowed","expected":true,"passed":true},{"actual":true,"check":"empty","expected":true,"passed":true},{"actual":true,"check":"switch","expected":true,"passed":true},{"actual":true,"check":"black third","expected":false,"passed":false},{"actual":true,"check":"alternating","expected":true,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"third same after balance\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"second allowed\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"empty\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"switch\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"black third\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"alternating\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":42.257,"exit_code":0,"observations":[{"actual":false,"check":"third same after balance","expected":false,"passed":true},{"actual":true,"check":"second allowed","expected":true,"passed":true},{"actual":true,"check":"empty","expected":true,"passed":true},{"actual":true,"check":"switch","expected":true,"passed":true},{"actual":false,"check":"black third","expected":false,"passed":true},{"actual":true,"check":"alternating","expected":true,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"third same after balance\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"second allowed\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"empty\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"switch\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"black third\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"alternating\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}