StepFun Launches Step 5 Preview: A 600B-Total, 27B-Active MoE Model With 1M Context for Long-Horizon Agentic Work

StepFun has released a preview of its Step 5 model, a sparse Mixture-of-Experts architecture featuring 600 billion total parameters and 27 billion active parameters. The multimodal model supports input for text, images, and video alongside a 1-million-token context window. Designed for long-horizon agentic tasks, it aims to assist users in fields like professional research and software development.