Proto is a betting-product surface at /v1/proto. Expand Fixtures & Prices for mapped fixture lists/detail and Rounds for betting-round metadata. Fixture reads require odds access and use the REST quota/rate-limit chain. Only mapped fixtures appear in canonical reads. Multiple source rows can merge into one canonical baseball, basketball, or soccer fixture, with their markets combined. Use the returned fixture ID and league to continue into the relevant sport’s game or match API. Read the Proto / Toto guide for provider status/type codes, epoch-millisecond filters, pagination, market fields, quote selection rules, and round metadata. Proto odds retain their product-specific shape.