{"abstract":"Zero quality excludes media candidates.","category":"Content negotiation","checks":4,"contract":"Bounded offline decision model: zero quality excludes media candidates. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.","contract_signature":"candidates","evaluation_group":"xh-zero-quality-excludes-media-candidates","failed_approach":"The attempted repair uses `[name for name,q in candidates if q >= 0]` and still violates a separate fixture.","family":"xh-zero-quality-excludes-media-candidates","id":"FA-6836","implementations":{"attempt":{"sha256":"0247298dbe8a3c87715ddc778288293219fb4310b5e701969182d01c5c1e5f34","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(candidates):\n    return [name for name,q in candidates if q >= 0]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve([('a', 0), ('b', 1)]), ['b'])\", \"check('fixture 2', solve([]), [])\", \"check('fixture 3', solve([('a', 0.1)]), ['a'])\", \"check('fixture 4', solve([('a', 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":"725ae18ec510abe05326ef7c1e235b020799e6f6e7f69239e5ec1e7f1ecdd44b","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(candidates):\n    return [name for name,q in candidates]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve([('a', 0), ('b', 1)]), ['b'])\", \"check('fixture 2', solve([]), [])\", \"check('fixture 3', solve([('a', 0.1)]), ['a'])\", \"check('fixture 4', solve([('a', 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-zero-quality-excludes-media-candidates","generated_at":"2026-09-29T14:38:05.620491+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic content negotiation model isolates the zero-quality-excludes-media-candidates policy at a network component boundary.","root_cause":"The faulty implementation uses `[name for name,q in candidates]` for the zero-quality-excludes-media-candidates decision.","sha256":"80ea8c453aebd83ce48f8155fc59e5dd758a7e450ef109ee80667340d3164c0f","title":"Zero quality excludes media candidates · 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":38.074,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":["a"],"check":"fixture 3","expected":["a"],"passed":true},{"actual":["a"],"check":"fixture 4","expected":[],"passed":false},{"actual":["a","b"],"check":"fixture 1","expected":["b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [\"a\"], \"expected\": [\"a\"], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": [\"a\", \"b\"], \"expected\": [\"b\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.078,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":["a"],"check":"fixture 3","expected":["a"],"passed":true},{"actual":["a"],"check":"fixture 4","expected":[],"passed":false},{"actual":["a","b"],"check":"fixture 1","expected":["b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [\"a\"], \"expected\": [\"a\"], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": [\"a\", \"b\"], \"expected\": [\"b\"], \"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."}}