`longmemeval_bench --float16` builds every per-question store with
MemoryConfig::float16, so the vector stage searches half-rounded
embeddings exactly as such a store holds them.
Full longmemeval_s (500 questions, ~494 turns each) with real
all-MiniLM-L6-v2 embeddings, f32 vs float16, on tank (CUDA): identical
at every Hit@k and MRR, turn and session level, in all eight modes —
bar RRF session MRR 0.9253 vs 0.9254 and one or two flips out of ~320
in which gold session ranks first. The f32 run reproduces the published
hybrid numbers exactly. The earlier float16 evidence was synthetic
clustered data only; this is the real-embedding check.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
