Reasoning Open weights

StepFun flash model for efficient multimodal reasoning, coding, and tool use

stepfun/step-3.5-flash-2603 2026-04-02 256K context $0.1/M input $0.3/M output
6 providers
Open weights

StepFun flash lane for quick multimodal reasoning and coding assistance

stepfun/step-3.5-flash 2026-01-29 256K context $0.1/M input $0.3/M output
14 providers