FW-DeepSeek-V3.1

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About this model

DeepSeek-V3.1 is post-trained on the top of DeepSeek-V3.1-Base, which is built upon the original V3 base checkpoint through a two-phase long context extension approach, following the methodology outlined in the original DeepSeek-V3 report. We have expanded our dataset by collecting additional long documents and substantially extending both training phases. The 32K extension phase has been increased 10-fold to 630B tokens, while the 128K extension phase has been extended by 3.3x to 209B tokens. Additionally, DeepSeek-V3.1 is trained using the UE8M0 FP8 scale data format to ensure compatibility with microscaling data formats.

Key model capabilities

• Dual-mode architecture with "thinking" and "non-thinking" chat modes for both fast inference and complex agentic behaviors
• Two-phase long context extension with 32K extension (630B tokens) and 128K extension (209B tokens)
• Trained using the UE8M0 FP8 scale data format for compatibility with microscaling data formats
• Function calling support including custom tools, code agents, search agents, and multi-turn tool use