FA-100546 / Mixture of experts dispatch / Open access
Equal gate scores route according to arrival order · case 01
Equal gate scores route according to arrival order.
ROOT CAUSE
A tie has no deterministic expert-level secondary key.
THE FAILURE
A tie has no deterministic expert-level secondary key.
Unsuccessful approach: Reversing the input list still reverses the selected expert.
Case contract
Choose the maximum-scoring expert; ties select the lexically smallest ID.
Why this case matters
A deterministic toy router makes this dispatch decision independently inspectable.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(scores):
return max(scores,key=lambda x:x[1])[0]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('reverse tie',solve([('z',N),('a',N)]),'a')
check('higher score',solve([('a',N),('b',N+1)]),'b')
check('three-way tie',solve([('c',0),('b',0),('a',0)]),'a')
check('negative',solve([('a',-N),('b',-N-1)]),'a')
check('singleton',solve([('q',N)]),'q')
check('permuted tie',solve([('b',N),('a',N)]),'a')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| reverse tie | z | a | Failed |
| higher score | b | b | Passed |
| three-way tie | c | a | Failed |
| negative | a | a | Passed |
| singleton | q | q | Passed |
| permuted tie | b | a | Failed |
SHA-256 / 2e9ad18c09efd4eb93c5e5f5e9ed6668a8f87673ab5133ce7a637b9680fd1df0
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(scores):
return sorted(scores,key=lambda x:-x[1])[0][0]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('reverse tie',solve([('z',N),('a',N)]),'a')
check('higher score',solve([('a',N),('b',N+1)]),'b')
check('three-way tie',solve([('c',0),('b',0),('a',0)]),'a')
check('negative',solve([('a',-N),('b',-N-1)]),'a')
check('singleton',solve([('q',N)]),'q')
check('permuted tie',solve([('b',N),('a',N)]),'a')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| reverse tie | z | a | Failed |
| higher score | b | b | Passed |
| three-way tie | c | a | Failed |
| negative | a | a | Passed |
| singleton | q | q | Passed |
| permuted tie | b | a | Failed |
SHA-256 / 61eb5cebe25ae8733440c404f9701d3b640e8e71ff80799d656798166b96240c
HELD IN THE MEMBER ARCHIVE
The verified repair and its recorded checks are member-only.
This mechanism has 6 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.
Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.
Member access is invitation-based. Sign in with your invited account to inspect the repair.
Sign in to the archive ↗Verification & scope
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.
Observations recorded using Python 3.12.14 at 2026-09-30T16:48:36.730485+00:00.
Case digest / 54eeeea084b07cb61e8dee2bacf696093a136318cfddbd8868a43a372aeb24f9