StepFun (Jieyue Xingchen) announced on October 12 that its flagship model Step 5 Preview has gone live on Tencent's all-scenario AI office workspace WorkBuddy, with exclusive limited-time free access from October 12 to October 25.
Launched on September 20, Step 5 Preview targets AI programming, software engineering, professional knowledge work, and finance scenarios, with improved performance on real-world agentic tasks. The model uses a sparse mixture-of-experts (MoE) architecture with 60 billion total parameters and 2.7 billion activated parameters, supports a 1-million-token context window, and natively handles both text and vision inputs. The full model weights are scheduled for open-sourcing on October 15.
On WorkBuddy, the model's reasoning and agent capabilities will help users handle deep research, information retrieval, data analysis, document and PPT generation, and other office tasks, with support for sustained execution of multi-step complex tasks.
Analysts see Tencent's move to integrate StepFun's latest model into its office scenario with limited-time free access as a signal of intensifying competition in the AI office track. For StepFun, tapping Tencent's office ecosystem is an important channel for its model capabilities to reach a massive consumer base. Whether users stay after the free period will depend on the model's real-world performance in office tasks.
