Introducing Hy4 Preview
Tencent’s Hy4 Preview is a 770B-parameter open-weight text model with a 1M-token context window.
Willison notes Hy4 is text-only, with 49B active parameters and a 1.56TB Hugging Face release. He contrasts it with July’s Hy3, which was smaller across parameters, active parameters, context, and download size. Its chat template appears to expose only two reasoning modes: default `high` and `no_think`. In his SVG test, the reasoning trace used clipped English, which he reads as possibly more token-efficient for hidden reasoning. Simon Willison's note
Willison notes Hy4 is text-only, with 49B active parameters and a 1.56TB Hugging Face release. He contrasts it with July’s Hy3, which was smaller across parameters, active parameters, context, and download size. Its chat template appears to expose only two reasoning modes: default `high` and `no_think`. In his SVG test, the reasoning trace used clipped English, which he reads as possibly more token-efficient for hidden reasoning. Simon Willison's note
score 8