DeepSeek V3.1: 840B token continued pretrain, beating Claude 4 Sonnet at 11% of its cost
DeepSeek released DeepSeek V3.1, a quietly rolled out open model with an 128K context window and improvements in token efficiency, coding, and agentic benchmarks. ByteDance launched the permissive Seed-OSS 36B model on Hugging Face, noted for long-context and reasoning capabilities. Zhipu AI introduced ComputerRL, a reinforcement learning framework for computer-use agents, achieving strong benchmark results. In developer tooling, GitHub Copilot expanded globally, Microsoft VS Code integrated Gemini 2.5 Pro and updated GPT-5 agent prompts, and Anthropic launched Claude Code seats with spend controls. Open-source fine-tuning advances include Together AI adding SFT for gpt-oss-120B/20B and Baseten enabling multinode 120B training with Truss CLI. The community noted mixed performance and ongoing post-training adjustments for DeepSeek V3.1.