{"abstract":"A vehicle is admitted without sufficient surveyed clearance in the controlled route-policy fixture.","category":"Navigation route constraints","checks":6,"contract":"All dimensions are integer centimeters. Unknown clearance is None and rejects travel; equality with height plus margin permits travel.","contract_signature":"height, margin, clearance","evaluation_group":"model-4e9fcba9de06cf20","failed_approach":"A strict comparison rejects exact equality even though the modeled threshold is inclusive.","family":"z-navigation_routes-clearance","id":"FA-12206","implementations":{"attempt":{"sha256":"cb7ff8fa0d0a28a97ee6ec66e12d1b23c6666d557b9af87a079b3972db065515","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(height, margin, clearance):\n    return clearance is not None and height + margin < clearance\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nh = 200 + N\ncheck('unknown survey', solve(h,10,None), False)\ncheck('margin omitted', solve(h,10,h+5), False)\ncheck('exact threshold', solve(h,10,h+10), True)\ncheck('above threshold', solve(h,10,h+11), True)\ncheck('physical collision', solve(h,0,h-1), False)\ncheck('zero margin equality', solve(h,0,h), True)\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":"60380caa8ff3e114a8ab2c6567f4608a43c8928c72419243c064b569ffda2142","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(height, margin, clearance):\n    return clearance is None or height <= clearance\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nh = 200 + N\ncheck('unknown survey', solve(h,10,None), False)\ncheck('margin omitted', solve(h,10,h+5), False)\ncheck('exact threshold', solve(h,10,h+10), True)\ncheck('above threshold', solve(h,10,h+11), True)\ncheck('physical collision', solve(h,0,h-1), False)\ncheck('zero margin equality', solve(h,0,h), True)\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":"Simplified deterministic offline policy model; not a production router or authoritative road guidance. 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":"z-navigation_routes-clearance","generated_at":"2026-09-29T14:38:54.880168+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Navigation policies depend on road context that a shortest-path cost alone does not encode.","root_cause":"Only physical height is compared, omitting the specified safety margin and treating unknown clearance as safe.","sha256":"5d8397961f64c3760d0c0ba4a90876de93bd68ba6b213a75c86897cd933aadd7","title":"A vehicle is admitted without sufficient surveyed clearance · 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":40.59,"exit_code":1,"observations":[{"actual":false,"check":"unknown survey","expected":false,"passed":true},{"actual":false,"check":"margin omitted","expected":false,"passed":true},{"actual":false,"check":"exact threshold","expected":true,"passed":false},{"actual":true,"check":"above threshold","expected":true,"passed":true},{"actual":false,"check":"physical collision","expected":false,"passed":true},{"actual":false,"check":"zero margin equality","expected":true,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"unknown survey\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"margin omitted\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"exact threshold\", \"actual\": false, \"expected\": true, \"passed\": false}, {\"check\": \"above threshold\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"physical collision\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"zero margin equality\", \"actual\": false, \"expected\": true, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.361,"exit_code":1,"observations":[{"actual":true,"check":"unknown survey","expected":false,"passed":false},{"actual":true,"check":"margin omitted","expected":false,"passed":false},{"actual":true,"check":"exact threshold","expected":true,"passed":true},{"actual":true,"check":"above threshold","expected":true,"passed":true},{"actual":false,"check":"physical collision","expected":false,"passed":true},{"actual":true,"check":"zero margin equality","expected":true,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"unknown survey\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"margin omitted\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"exact threshold\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"above threshold\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"physical collision\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"zero margin equality\", \"actual\": true, \"expected\": true, \"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."}}