{"abstract":"HEAD retains full representation metadata while suppressing the body.","category":"HTTP ranges","checks":6,"contract":"Only GET honors the already resolved range. HEAD returns [200,full-length,empty], GET [206,part-length,part]. Inputs are ASCII strings.","contract_signature":"method, full, part","evaluation_group":"s3-http_ranges-conditional","failed_approach":"The partial repair uses return [206,len(part),part] if method == \"GET\" else [200,len(part),\"\"], which still violates the stated contract.","family":"s3-http_ranges-head-ignores-range-body","id":"FA-26386","implementations":{"attempt":{"sha256":"b275004825db95441095401aecd11280310a4a8b1ae5e9a1ce97d51ba870adf0","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(method, full, part):\n    return [206,len(part),part] if method == \"GET\" else [200,len(part),\"\"]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('head-ignores-range-body fixture 0', solve(\"HEAD\",\"abc\"*N,\"b\"*N), [200,3*N,\"\"])\ncheck('head-ignores-range-body fixture 1', solve(\"GET\",\"abc\"*N,\"b\"*N), [206,N,\"b\"*N])\ncheck('head-ignores-range-body fixture 2', solve(\"HEAD\",\"\",\"\"), [200,0,\"\"])\ncheck('head-ignores-range-body fixture 3', solve(\"HEAD\",\"abcd\",\"\"), [200,4,\"\"])\ncheck('head-ignores-range-body fixture 4', solve(\"GET\",\"abcd\",\"\"), [206,0,\"\"])\ncheck('head-ignores-range-body fixture 5', solve(\"GET\",\"abcd\",\"abcd\"), [206,4,\"abcd\"])\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":"2289a7777fffa89d2a78a4bfed65b78c9a02aa127b58efcf0f0fe19d6a193f26","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(method, full, part):\n    return [206,len(part),part] if method == \"GET\" else [206,len(part),\"\"]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('head-ignores-range-body fixture 0', solve(\"HEAD\",\"abc\"*N,\"b\"*N), [200,3*N,\"\"])\ncheck('head-ignores-range-body fixture 1', solve(\"GET\",\"abc\"*N,\"b\"*N), [206,N,\"b\"*N])\ncheck('head-ignores-range-body fixture 2', solve(\"HEAD\",\"\",\"\"), [200,0,\"\"])\ncheck('head-ignores-range-body fixture 3', solve(\"HEAD\",\"abcd\",\"\"), [200,4,\"\"])\ncheck('head-ignores-range-body fixture 4', solve(\"GET\",\"abcd\",\"\"), [206,0,\"\"])\ncheck('head-ignores-range-body fixture 5', solve(\"GET\",\"abcd\",\"abcd\"), [206,4,\"abcd\"])\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":"Deterministic simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP implementation. 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":"s3-http_ranges-head-ignores-range-body","generated_at":"2026-09-29T14:41:15.635934+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Range responses combine representation identity, conditional requests, framing, and partial-object state.","root_cause":"The head-ignores-range-body decision uses return [206,len(part),part] if method == \"GET\" else [206,len(part),\"\"].","sha256":"ffe0ca41df472f5c69b65d7c36e74dfe892b2e21e3f37fc08354b42a56f67e8a","title":"HEAD retains full representation metadata while suppressing the body · 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":41.149,"exit_code":1,"observations":[{"actual":[200,1,""],"check":"head-ignores-range-body fixture 0","expected":[200,3,""],"passed":false},{"actual":[206,1,"b"],"check":"head-ignores-range-body fixture 1","expected":[206,1,"b"],"passed":true},{"actual":[200,0,""],"check":"head-ignores-range-body fixture 2","expected":[200,0,""],"passed":true},{"actual":[200,0,""],"check":"head-ignores-range-body fixture 3","expected":[200,4,""],"passed":false},{"actual":[206,0,""],"check":"head-ignores-range-body fixture 4","expected":[206,0,""],"passed":true},{"actual":[206,4,"abcd"],"check":"head-ignores-range-body fixture 5","expected":[206,4,"abcd"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"head-ignores-range-body fixture 0\", \"actual\": [200, 1, \"\"], \"expected\": [200, 3, \"\"], \"passed\": false}, {\"check\": \"head-ignores-range-body fixture 1\", \"actual\": [206, 1, \"b\"], \"expected\": [206, 1, \"b\"], \"passed\": true}, {\"check\": \"head-ignores-range-body fixture 2\", \"actual\": [200, 0, \"\"], \"expected\": [200, 0, \"\"], \"passed\": true}, {\"check\": \"head-ignores-range-body fixture 3\", \"actual\": [200, 0, \"\"], \"expected\": [200, 4, \"\"], \"passed\": false}, {\"check\": \"head-ignores-range-body fixture 4\", \"actual\": [206, 0, \"\"], \"expected\": [206, 0, \"\"], \"passed\": true}, {\"check\": \"head-ignores-range-body fixture 5\", \"actual\": [206, 4, \"abcd\"], \"expected\": [206, 4, \"abcd\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":37.527,"exit_code":1,"observations":[{"actual":[206,1,""],"check":"head-ignores-range-body fixture 0","expected":[200,3,""],"passed":false},{"actual":[206,1,"b"],"check":"head-ignores-range-body fixture 1","expected":[206,1,"b"],"passed":true},{"actual":[206,0,""],"check":"head-ignores-range-body fixture 2","expected":[200,0,""],"passed":false},{"actual":[206,0,""],"check":"head-ignores-range-body fixture 3","expected":[200,4,""],"passed":false},{"actual":[206,0,""],"check":"head-ignores-range-body fixture 4","expected":[206,0,""],"passed":true},{"actual":[206,4,"abcd"],"check":"head-ignores-range-body fixture 5","expected":[206,4,"abcd"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"head-ignores-range-body fixture 0\", \"actual\": [206, 1, \"\"], \"expected\": [200, 3, \"\"], \"passed\": false}, {\"check\": \"head-ignores-range-body fixture 1\", \"actual\": [206, 1, \"b\"], \"expected\": [206, 1, \"b\"], \"passed\": true}, {\"check\": \"head-ignores-range-body fixture 2\", \"actual\": [206, 0, \"\"], \"expected\": [200, 0, \"\"], \"passed\": false}, {\"check\": \"head-ignores-range-body fixture 3\", \"actual\": [206, 0, \"\"], \"expected\": [200, 4, \"\"], \"passed\": false}, {\"check\": \"head-ignores-range-body fixture 4\", \"actual\": [206, 0, \"\"], \"expected\": [206, 0, \"\"], \"passed\": true}, {\"check\": \"head-ignores-range-body fixture 5\", \"actual\": [206, 4, \"abcd\"], \"expected\": [206, 4, \"abcd\"], \"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."}}