Tencent has released and open-sourced Tencent Hy4 preview, a next-generation large language model with 770B total parameters and 49B active parameters, featuring a context window exceeding 1M tokens. Designed for real-world productivity tasks, Hy4 preview excels in coding, office work, and scientific research. It is now accessible via Work Buddy, Code Buddy, Yuanbao, ima, and other Tencent products, as well as through API on Tencent Cloud Token Hub and Open Router.

Free access is available on Work Buddy and Code Buddy for two weeks, with Hy3 access extended until September 30. In internal blind evaluations involving 163 experts and 203 engineering tasks, Hy4 preview scored 2.99 out of 4.00, outperforming GLM-5.3 (2.92) and Kimi K3 (2.94). The model was trained on high-quality data co-created with Tencent experts across software engineering, gaming, finance, and security, and optimized through deep co-design with products like Work Buddy.

Hy4 preview enhances long-context development, front-end quality, financial analysis, data workflows, game prototyping, and scientific reasoning. Notably, it contributed to its own development by participating in automated optimization of training methods, data strategies, and inference systems, boosting end-to-end throughput by 31.8%. This establishes an early recursive self-improvement loop, marking a significant advance in open-source AI intelligence.