Step 5 Preview: Advancing the Pareto Frontier

  > Built on a sparse Mixture-of-Experts architecture, Step 5 Preview has 600B total parameters, with 27B active per token, and supports a 1M-token context window and vision input.

  > Step 5 Preview scores 44 on the Artificial Analysis Intelligence Index.

  > The model will be released with open weights on October 15.

I guess being Chinese company they decided to skip version 4, while also giving impression to be on the similar iteration with leading companies (claude opus 5). I wonder if other Chinese labs like Kimi/Moonshot will follow suit.

> Without any Pokémon-specific optimization, Step 5 Preview has so far sustained progress for more than 3,000 turns and 6 million tokens of interaction. By turn 3,082, it had unlocked Cut, earned three Gym Badges, and defeated Lt. Surge. The run is now roughly one-third of the way through the main story.

Finally FireRed is being used as a benchmark again! I believe Astra can beat it in 18 hours. Not sure how that compares.

IT's Artificial Analysis Index is the same as Kimi K3, which is about 4.6x bigger, and GLM 5.3, which is about 1.25x bigger. Pricing is $1/$2.70 i/o. Openweights on October 15.

Their posisitoning is nice. Instead of saying they are cheaper and a bit less performant (in terms of intelligence), they say they are best among the cheaper and a bit less performant ones.

For anyone else looking for the pricing: https://platform.stepfun.ai/docs/en/guides/pricing/details#p...

How about adding a contested historical facts benchmark?

Huh wonder why they skipped 4?