2 tracked versions of the Yi family. Timeline ordered newest → oldest. Flagship version marked.
Yi Lightning is 01.AI's cost-efficient flagship — consistently top-5 on LMArena Chinese leaderboards at a fraction of GPT-4o pricing. Fast inference makes it a strong candidate for chat agents.
Yi-1.5-34B-Chat is 01.AI's open-weight chat checkpoint in the Yi-1.5 family. It is distinct from the separately named Yi-Large API model. The official model card provides weights and licensing information.
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