{"abstract":"Flags after the first rejection are counted as accepted.","category":"Speculative decoding bookkeeping","checks":7,"contract":"Return the number of consecutive true flags from the beginning.","contract_signature":"flags","evaluation_group":"spec-accepted-mask-prefix","failed_approach":"Requiring all flags to be true returns zero for a partially accepted prefix.","family":"w3-speculative-decoding-bookkeeping-accepted-mask-prefix","id":"FA-100716","implementations":{"attempt":{"sha256":"5d5631ed2c277e2dbca63c895b678a26ab6c04d8d1e3d21ae082a03f4356bb9b","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(flags):\n    return len(flags) if all(flags) else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('hole stops', solve([True,False,True]),1)\ncheck('all accepted', solve([True]*N),N)\ncheck('reject first', solve([False,True]),0)\ncheck('empty flags', solve([]),0)\ncheck('singleton true', solve([True]),1)\ncheck('singleton false', solve([False]),0)\ncheck('later false', solve([True,True,False,True]),2)\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":"a9922b5aee5e588a0a08ead8e5417ae02d323f6ca4c6153650ae3e4d55d35115","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(flags):\n    return sum(bool(v) for v in flags)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('hole stops', solve([True,False,True]),1)\ncheck('all accepted', solve([True]*N),N)\ncheck('reject first', solve([False,True]),0)\ncheck('empty flags', solve([]),0)\ncheck('singleton true', solve([True]),1)\ncheck('singleton false', solve([False]),0)\ncheck('later false', solve([True,True,False,True]),2)\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":"These are finite toy sequences with explicit contracts; they make no claim about production decoder behavior or model quality. 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":"w3-speculative-decoding-bookkeeping-accepted-mask-prefix","generated_at":"2026-09-30T16:48:38.598007+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A self-contained bookkeeping model makes prefix and token-count semantics observable without a model runtime.","root_cause":"True flags after a rejected position are counted as accepted.","sha256":"50fa91b93df15c45f27f90f249399728196a5927e4cbe9e30e3eb71a49fe7048","title":"Decoding: Flags after the first rejection are counted as accepted · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":31.925,"exit_code":1,"observations":[{"actual":0,"check":"hole stops","expected":1,"passed":false},{"actual":1,"check":"all accepted","expected":1,"passed":true},{"actual":0,"check":"reject first","expected":0,"passed":true},{"actual":0,"check":"empty flags","expected":0,"passed":true},{"actual":1,"check":"singleton true","expected":1,"passed":true},{"actual":0,"check":"singleton false","expected":0,"passed":true},{"actual":0,"check":"later false","expected":2,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"hole stops\", \"actual\": 0, \"expected\": 1, \"passed\": false}, {\"check\": \"all accepted\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"reject first\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"empty flags\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"singleton true\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"singleton false\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"later false\", \"actual\": 0, \"expected\": 2, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":30.511,"exit_code":1,"observations":[{"actual":2,"check":"hole stops","expected":1,"passed":false},{"actual":1,"check":"all accepted","expected":1,"passed":true},{"actual":1,"check":"reject first","expected":0,"passed":false},{"actual":0,"check":"empty flags","expected":0,"passed":true},{"actual":1,"check":"singleton true","expected":1,"passed":true},{"actual":0,"check":"singleton false","expected":0,"passed":true},{"actual":3,"check":"later false","expected":2,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"hole stops\", \"actual\": 2, \"expected\": 1, \"passed\": false}, {\"check\": \"all accepted\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"reject first\", \"actual\": 1, \"expected\": 0, \"passed\": false}, {\"check\": \"empty flags\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"singleton true\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"singleton false\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"later false\", \"actual\": 3, \"expected\": 2, \"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."}}