Introducing Step 5 Preview: Advancing the Pareto Frontier.
This is a dev post classified by Jev as AI dev tools (a launch), kept by the Dev Radar because it carries real work, not commentary.
Introducing Step 5 Preview: Advancing the Pareto Frontier. Step 5 Preview is our new flagship model for agentic work, delivering frontier-level performance across software engineering and professional knowledge work, with particular strength in finance. - 600B total / 27B active MoE, with 1M context + Vision - Substantially lower task cost at comparable intelligence - Broad software engineering capabilities with sustained execution over long horizons Try Step 5 Preview: https://platform.stepfun.ai Model page: https://www.stepfun.com/step-5-preview Open weights on Oct 15.
Posted by StepFun (12.6k followers) 1 h ago · 305 likes · 10.6k views · view the original post on X. Kept by the Dev Radar as AI dev tools. Tools mentioned: StepFun Open Platform.
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