DeepSeek-V3.1 Released: What Are the Key Updates?

TradingKey - On the afternoon of August 21, 2025, Beijing time, DeepSeek officially launched the DeepSeek-V3.1 model. By adopting a new hybrid reasoning architecture and enhanced Agent capabilities, the model achieves significant performance improvements in tasks such as code repair and command-line terminal operations.

According to DeepSeek’s official announcement, the key updates in the new model include:

1. Hybrid inference: Think & Non-Think — one model, two modes
2. Faster thinking: DeepSeek-V3.1-Think reaches answers in less time vs. DeepSeek-R1-0528
3. Stronger agent skills: Post-training boosts tool use and multi-step agent tasks

The DeepSeek API has been upgraded in parallel:

• deepseek-chat: corresponds to the non-thinking mode
• deepseek-reasoner: corresponds to the thinking mode
• Context length has been extended to 128K

The introduction of the hybrid reasoning architecture is widely seen as the core upgrade of this release. DeepSeek noted:

“Our first step toward the agent era.”

In official demonstrations of programming agent capabilities, DeepSeek-V3.1 achieved significantly higher scores than previous models in complex task evaluations, including code repair and command-line terminal testing.

Source: DeepSeek

Some AI-savvy netizens commented that if this update is merely an experimental integration of chat and reasoning models, it represents a solid incremental improvement. Compared to deploying two separate models, this unified architecture saves considerable deployment and operational effort and improves computational efficiency.

However, the latest model still exhibits issues such as AI hallucinations and mixed Chinese-English output. The industry continues to anticipate a major upgrade in the upcoming V4 or R2 model.