The bare-tail tie-break ranked candidates by prompt price alone, so two
entries sharing a tail where one is cheaper on prompt but far dearer on
completion could resolve to the entry that undercharges output-heavy
traffic — contradicting the "highest-priced wins for money safety" promise.
Rank by the combined prompt + completion per-token cost instead, so the
choice stays deterministic and money-safe whichever way traffic leans. As
before there are zero bare-tail collisions in the live feed, so this changes
no resolved price today; it only governs the latent case.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>