{"abstract":"Repeated expert contributions are not merged per token.","category":"Mixture of experts dispatch","checks":6,"contract":"For [token,expert,weighted_value] rows, aggregate values by (token,expert), sorted by token then expert.","contract_signature":"routes","evaluation_group":"moe-route-contribution-merge","failed_approach":"Keeping only the final contribution drops earlier route mass.","family":"w3-mixture-of-experts-dispatch-route-value-merge","id":"FA-100626","implementations":{"attempt":{"sha256":"378857e6684e8ddec473666aad182419b2f90eb98aed2b56af73e51a3dc925a4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(routes):\n    d={}\n    for t,e,v in routes: d[(t,e)]=v\n    return [[t,e,v] for (t,e),v in sorted(d.items())]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\na='a'+str(N); rows=[[0,a,N],[0,a,2*N],[1,a,N]]\ncheck('same pair summed',solve(rows),[[0,a,3*N],[1,a,N]])\ncheck('distinct experts',solve([[0,'b',N],[0,'a',N]]),[[0,'a',N],[0,'b',N]])\ncheck('empty',solve([]),[])\ncheck('negative contribution',solve([[0,'x',N],[0,'x',-1]]),[[0,'x',N-1]])\ncheck('singleton',solve([[N,'x',N]]),[[N,'x',N]])\ncheck('two tokens',solve([[1,'x',2],[0,'x',3]]),[[0,'x',3],[1,'x',2]])\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":"f87f34b13e335b3fde0a1e4368b7b7c2b2c2edb2c004fff915ca6edf3f9aa7ee","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(routes):\n    return sorted(routes,key=lambda r:(r[0],r[1]))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\na='a'+str(N); rows=[[0,a,N],[0,a,2*N],[1,a,N]]\ncheck('same pair summed',solve(rows),[[0,a,3*N],[1,a,N]])\ncheck('distinct experts',solve([[0,'b',N],[0,'a',N]]),[[0,'a',N],[0,'b',N]])\ncheck('empty',solve([]),[])\ncheck('negative contribution',solve([[0,'x',N],[0,'x',-1]]),[[0,'x',N-1]])\ncheck('singleton',solve([[N,'x',N]]),[[N,'x',N]])\ncheck('two tokens',solve([[1,'x',2],[0,'x',3]]),[[0,'x',3],[1,'x',2]])\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":"Inputs are finite toy scores and routes; the contract does not model a production model, accelerator, or learned routing quality. 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":"w3-mixture-of-experts-dispatch-route-value-merge","generated_at":"2026-09-30T16:48:37.646356+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic toy router makes this dispatch decision independently inspectable.","root_cause":"The same expert is evaluated more than once after route union.","sha256":"41c56188751c7bdf28b2d6b2263ba1eb8b44b297dc47f3c5d86f106d137d6bc7","title":"Repeated expert contributions are not merged per token · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":29.726,"exit_code":1,"observations":[{"actual":[[0,"a1",2],[1,"a1",1]],"check":"same pair summed","expected":[[0,"a1",3],[1,"a1",1]],"passed":false},{"actual":[[0,"a",1],[0,"b",1]],"check":"distinct experts","expected":[[0,"a",1],[0,"b",1]],"passed":true},{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[[0,"x",-1]],"check":"negative contribution","expected":[[0,"x",0]],"passed":false},{"actual":[[1,"x",1]],"check":"singleton","expected":[[1,"x",1]],"passed":true},{"actual":[[0,"x",3],[1,"x",2]],"check":"two tokens","expected":[[0,"x",3],[1,"x",2]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"same pair summed\", \"actual\": [[0, \"a1\", 2], [1, \"a1\", 1]], \"expected\": [[0, \"a1\", 3], [1, \"a1\", 1]], \"passed\": false}, {\"check\": \"distinct experts\", \"actual\": [[0, \"a\", 1], [0, \"b\", 1]], \"expected\": [[0, \"a\", 1], [0, \"b\", 1]], \"passed\": true}, {\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"negative contribution\", \"actual\": [[0, \"x\", -1]], \"expected\": [[0, \"x\", 0]], \"passed\": false}, {\"check\": \"singleton\", \"actual\": [[1, \"x\", 1]], \"expected\": [[1, \"x\", 1]], \"passed\": true}, {\"check\": \"two tokens\", \"actual\": [[0, \"x\", 3], [1, \"x\", 2]], \"expected\": [[0, \"x\", 3], [1, \"x\", 2]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":29.605,"exit_code":1,"observations":[{"actual":[[0,"a1",1],[0,"a1",2],[1,"a1",1]],"check":"same pair summed","expected":[[0,"a1",3],[1,"a1",1]],"passed":false},{"actual":[[0,"a",1],[0,"b",1]],"check":"distinct experts","expected":[[0,"a",1],[0,"b",1]],"passed":true},{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[[0,"x",1],[0,"x",-1]],"check":"negative contribution","expected":[[0,"x",0]],"passed":false},{"actual":[[1,"x",1]],"check":"singleton","expected":[[1,"x",1]],"passed":true},{"actual":[[0,"x",3],[1,"x",2]],"check":"two tokens","expected":[[0,"x",3],[1,"x",2]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"same pair summed\", \"actual\": [[0, \"a1\", 1], [0, \"a1\", 2], [1, \"a1\", 1]], \"expected\": [[0, \"a1\", 3], [1, \"a1\", 1]], \"passed\": false}, {\"check\": \"distinct experts\", \"actual\": [[0, \"a\", 1], [0, \"b\", 1]], \"expected\": [[0, \"a\", 1], [0, \"b\", 1]], \"passed\": true}, {\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"negative contribution\", \"actual\": [[0, \"x\", 1], [0, \"x\", -1]], \"expected\": [[0, \"x\", 0]], \"passed\": false}, {\"check\": \"singleton\", \"actual\": [[1, \"x\", 1]], \"expected\": [[1, \"x\", 1]], \"passed\": true}, {\"check\": \"two tokens\", \"actual\": [[0, \"x\", 3], [1, \"x\", 2]], \"expected\": [[0, \"x\", 3], [1, \"x\", 2]], \"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."}}