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Step 3.7 Flash Thinking

Step 3.7 Flash Thinking is StepFun's high-efficiency multimodal MoE model with visible reasoning enabled for deeper agentic coding, long-context reasoning, tool use, and native image/video understanding. ⚠️ Note: This model routes through StepFun, so privacy and logging guarantees may be limited.

Step 3.5 Flash 2603

Step 3.5 Flash 2603 is optimized for high-frequency agentic and coding workflows with improved token efficiency and faster reasoning. NOTE: This model runs via StepFun, which may log and train on your prompts.

Step 3.5 Flash

StepFun's most capable open-source reasoning model with visible reasoning traces. Built on a sparse Mixture-of-Experts architecture with 196B total parameters and only 11B active per token, it achieves frontier-level performance in math, logic, and agentic coding while reaching up to 350 tokens/sec. Supports 256K context. NOTE: This model runs via StepFun, which may log and train on your prompts.

Clef

Typed Choice, Score and Noul decisions. Use /v1/decisions or /v1/systemone; text-only questions compatibility is available through Chat Completions, Messages and Responses. Accepts inline images through the Cloudflare endpoint. Text admission is limited to 1,800 estimated tokens to avoid upstream truncation; up to four images, each at most 512 by 512 pixels. Input tokens are billed; output is free.

Clef Flash

Typed Choice, Score and Noul decisions. Use /v1/decisions or /v1/systemone; text-only questions compatibility is available through Chat Completions, Messages and Responses. Accepts inline images through the Cloudflare endpoint. Text admission is limited to 1,800 estimated tokens to avoid upstream truncation; up to four images, each at most 512 by 512 pixels. Input tokens are billed; output is free.

Gemma 4 26B A4B Chimera X Heretic

Chimera X Heretic is a Gemma 4 26B A4B multimodal mixture-of-experts fine-tune for creative writing, expressive dialogue, and roleplay.