{"abstract":"Parameter specificity counts matched constraints.","category":"Content negotiation","checks":4,"contract":"Bounded offline decision model: parameter specificity counts matched constraints. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.","evaluation_group":"xh-parameter-specificity-counts-matched-constraints","failed_approach":"The attempted repair uses `len(required)` and still violates a separate fixture.","family":"xh-parameter-specificity-counts-matched-constraints","id":"FA-6941","implementations":{"attempt":{"sha256":"a01a628b60fdd6cce1e57d74c132d0b837cd36d491a457b53eb8eaf19c71a6a4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(required, actual):\n    return len(required)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 1, 'b': 3, 'c': 4}), 1)\", \"check('fixture 2', solve({}, {'x': 1}), 0)\", \"check('fixture 3', solve({'a': 1}, {'a': 1}), 1)\", \"check('fixture 4', solve({'a': 1}, {}), 0)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\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":"4fc5a657aae69ed703437d516e416d8bc8d38db2f8983f6869da2777262cd6ee","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(required, actual):\n    return len(actual)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 1, 'b': 3, 'c': 4}), 1)\", \"check('fixture 2', solve({}, {'x': 1}), 0)\", \"check('fixture 3', solve({'a': 1}, {'a': 1}), 1)\", \"check('fixture 4', solve({'a': 1}, {}), 0)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\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":"6f2bb9badaec73ab23b09bf827acfe3d9e642ad8dbfcefb83be47384f10c7528","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(required, actual):\n    return sum(actual.get(k)==v for k,v in required.items())\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 1, 'b': 3, 'c': 4}), 1)\", \"check('fixture 2', solve({}, {'x': 1}), 0)\", \"check('fixture 3', solve({'a': 1}, {'a': 1}), 1)\", \"check('fixture 4', solve({'a': 1}, {}), 0)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\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":"Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. 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":"xh-parameter-specificity-counts-matched-constraints","generated_at":"2026-09-29T14:38:06.798982+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic content negotiation model isolates the parameter-specificity-counts-matched-constraints policy at a network component boundary.","repair":"Apply the explicit parameter-specificity-counts-matched-constraints contract, including the tested boundary and negative cases.","root_cause":"The faulty implementation uses `len(actual)` for the parameter-specificity-counts-matched-constraints decision.","sha256":"64847fa3344142171d1776af86844c0b11beeb6f33fdbdb1cc1711862293b8bc","title":"Parameter specificity counts matched constraints · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":35.116,"exit_code":1,"observations":[{"actual":0,"check":"fixture 2","expected":0,"passed":true},{"actual":1,"check":"fixture 3","expected":1,"passed":true},{"actual":1,"check":"fixture 4","expected":0,"passed":false},{"actual":2,"check":"fixture 1","expected":1,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 1, \"expected\": 0, \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": 2, \"expected\": 1, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":33.642,"exit_code":1,"observations":[{"actual":1,"check":"fixture 2","expected":0,"passed":false},{"actual":1,"check":"fixture 3","expected":1,"passed":true},{"actual":0,"check":"fixture 4","expected":0,"passed":true},{"actual":3,"check":"fixture 1","expected":1,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 1, \"expected\": 0, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": 3, \"expected\": 1, \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":34.814,"exit_code":0,"observations":[{"actual":0,"check":"fixture 2","expected":0,"passed":true},{"actual":1,"check":"fixture 3","expected":1,"passed":true},{"actual":0,"check":"fixture 4","expected":0,"passed":true},{"actual":1,"check":"fixture 1","expected":1,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": 1, \"expected\": 1, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}