{"abstract":"Different instruments collide by omitting the metric name.","category":"Observability","checks":6,"contract":"A series identity includes metric name, sorted label key-value pairs excluding configured dropped keys, measurement unit, and instrument kind. Dropping values never drops other equal-valued labels.","contract_signature":"name, labels, dropped, unit, kind","evaluation_group":"xt-metric-series","failed_approach":"The attempted repair substitutes return ('metric',. Fixture 1 still yields ('metric', (('a', '2'), ('z', '1')), 'count', 'counter') instead of ('requests', (('a', '2'), ('z', '1')), 'count', 'counter').","family":"xt-metric-series-metric-name","id":"FA-10256","implementations":{"attempt":{"sha256":"5ab981fbb0b15c1ef4e162dbc8a3750e66164daff4cb803a393394b00f0639fb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(name, labels, dropped, unit, kind):\n    return ('metric', tuple(sorted((k,v) for k,v in labels.items() if k not in dropped)), unit, kind)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve('requests', {'z': '1', 'a': '2'}, [], 'count', 'counter'), ('requests', (('a', '2'), ('z', '1')), 'count', 'counter'))\ncheck('fixture 2', solve('requests', {'a': '2', 'z': '1'}, [], 'count', 'counter'), ('requests', (('a', '2'), ('z', '1')), 'count', 'counter'))\ncheck('fixture 3', solve('requests', {'a': '2', 'z': '1'}, ['z'], 'count', 'counter'), ('requests', (('a', '2'),), 'count', 'counter'))\ncheck('fixture 4', solve('requests', {'a': 'same', 'b': 'same'}, ['a'], 'count', 'counter'), ('requests', (('b', 'same'),), 'count', 'counter'))\ncheck('fixture 5', solve('latency', {}, [], 'seconds', 'histogram'), ('latency', (), 'seconds', 'histogram'))\ncheck('fixture 6', solve('latency', {}, [], 'milliseconds', 'gauge'), ('latency', (), 'milliseconds', 'gauge'))\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":"24a816ee21d7f6e2a7fba6376dde5bc7b2173511f21d3eb1c9d89d8eb080c661","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(name, labels, dropped, unit, kind):\n    return (None, tuple(sorted((k,v) for k,v in labels.items() if k not in dropped)), unit, kind)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve('requests', {'z': '1', 'a': '2'}, [], 'count', 'counter'), ('requests', (('a', '2'), ('z', '1')), 'count', 'counter'))\ncheck('fixture 2', solve('requests', {'a': '2', 'z': '1'}, [], 'count', 'counter'), ('requests', (('a', '2'), ('z', '1')), 'count', 'counter'))\ncheck('fixture 3', solve('requests', {'a': '2', 'z': '1'}, ['z'], 'count', 'counter'), ('requests', (('a', '2'),), 'count', 'counter'))\ncheck('fixture 4', solve('requests', {'a': 'same', 'b': 'same'}, ['a'], 'count', 'counter'), ('requests', (('b', 'same'),), 'count', 'counter'))\ncheck('fixture 5', solve('latency', {}, [], 'seconds', 'histogram'), ('latency', (), 'seconds', 'histogram'))\ncheck('fixture 6', solve('latency', {}, [], 'milliseconds', 'gauge'), ('latency', (), 'milliseconds', 'gauge'))\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":" 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":"xt-metric-series-metric-name","generated_at":"2026-09-29T14:38:37.493318+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"An offline model of metric series identity, suitable for testing build and release tooling without external services.","root_cause":"The implementation substitutes return (None, for return (name,, so different instruments collide by omitting the metric name.","sha256":"140248a01b7e46b053c330416d61e1e62b1af1f30862a9c1df0c64e144c1fd17","title":"Metric series identity: Different instruments collide by omitting the metric name · 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":42.351,"exit_code":1,"observations":[{"actual":["metric",[["a","2"],["z","1"]],"count","counter"],"check":"fixture 1","expected":["requests",[["a","2"],["z","1"]],"count","counter"],"passed":false},{"actual":["metric",[["a","2"],["z","1"]],"count","counter"],"check":"fixture 2","expected":["requests",[["a","2"],["z","1"]],"count","counter"],"passed":false},{"actual":["metric",[["a","2"]],"count","counter"],"check":"fixture 3","expected":["requests",[["a","2"]],"count","counter"],"passed":false},{"actual":["metric",[["b","same"]],"count","counter"],"check":"fixture 4","expected":["requests",[["b","same"]],"count","counter"],"passed":false},{"actual":["metric",[],"seconds","histogram"],"check":"fixture 5","expected":["latency",[],"seconds","histogram"],"passed":false},{"actual":["metric",[],"milliseconds","gauge"],"check":"fixture 6","expected":["latency",[],"milliseconds","gauge"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [\"metric\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [\"metric\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [\"metric\", [[\"a\", \"2\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [\"metric\", [[\"b\", \"same\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"b\", \"same\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 5\", \"actual\": [\"metric\", [], \"seconds\", \"histogram\"], \"expected\": [\"latency\", [], \"seconds\", \"histogram\"], \"passed\": false}, {\"check\": \"fixture 6\", \"actual\": [\"metric\", [], \"milliseconds\", \"gauge\"], \"expected\": [\"latency\", [], \"milliseconds\", \"gauge\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":43.625,"exit_code":1,"observations":[{"actual":[null,[["a","2"],["z","1"]],"count","counter"],"check":"fixture 1","expected":["requests",[["a","2"],["z","1"]],"count","counter"],"passed":false},{"actual":[null,[["a","2"],["z","1"]],"count","counter"],"check":"fixture 2","expected":["requests",[["a","2"],["z","1"]],"count","counter"],"passed":false},{"actual":[null,[["a","2"]],"count","counter"],"check":"fixture 3","expected":["requests",[["a","2"]],"count","counter"],"passed":false},{"actual":[null,[["b","same"]],"count","counter"],"check":"fixture 4","expected":["requests",[["b","same"]],"count","counter"],"passed":false},{"actual":[null,[],"seconds","histogram"],"check":"fixture 5","expected":["latency",[],"seconds","histogram"],"passed":false},{"actual":[null,[],"milliseconds","gauge"],"check":"fixture 6","expected":["latency",[],"milliseconds","gauge"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [null, [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [null, [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"], [\"z\", \"1\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [null, [[\"a\", \"2\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"a\", \"2\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [null, [[\"b\", \"same\"]], \"count\", \"counter\"], \"expected\": [\"requests\", [[\"b\", \"same\"]], \"count\", \"counter\"], \"passed\": false}, {\"check\": \"fixture 5\", \"actual\": [null, [], \"seconds\", \"histogram\"], \"expected\": [\"latency\", [], \"seconds\", \"histogram\"], \"passed\": false}, {\"check\": \"fixture 6\", \"actual\": [null, [], \"milliseconds\", \"gauge\"], \"expected\": [\"latency\", [], \"milliseconds\", \"gauge\"], \"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."}}