Dated rates × immutable usage

A cost claim needs
a price-time receipt.

Provider prices change. Discounts and cached tokens complicate the arithmetic. Bind every benchmark cost to the exact rate card used—without uploading your usage log.

uncached input × input rate+cached input × cache rate+output × output rate

01 / Evidence

Usage and rate card

Local-only: neither file leaves this browser.

02 / Receipt

Repricing result

Usage SHA-256—
Rate card SHA-256—

03 / Why

Keep tokens fixed. Reprice history honestly.

Freeze evidence Preserve raw token counts and the exact rate-card snapshot.

Separate cache Cached input may have a different price from uncached input.

Show assumptions Effective date, retrieval time, source, currency, and unit stay in the receipt.