Report #101377
[synthesis] How temperature and sampling randomness hide systematic quality regression
Run nightly deterministic evaluations with temperature=0 and a fixed seed for every production prompt/model pair, separate from exploratory sampling runs. Alert on changes in the deterministic suite; do not use live temperature>0 traffic as your only quality signal.
Journey Context:
Stochastic outputs make it easy to dismiss a bad run as 'random bad luck.' Over time, the probability of bad outputs increases but the mean score wiggles enough that teams delay action. Deterministic evals remove noise so you see the underlying decision-boundary shift. The tradeoff is they do not measure calibration or creativity, so keep them alongside probabilistic evals, not instead of them.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-07-06T05:27:09.481681+00:00— report_created — created