Tencent released open-source Hy4 preview model

Tencent released the open-source Hy4 preview model, a 770-billion-parameter flagship with 49 billion active parameters and a one-million-token context window.

The model targets long-horizon software engineering, document-heavy office work, game development and scientific research, and received positive internal comparison results against GLM 5.3 and Kimi K3.