Hunyuan-A13B Technical Report

Hunyuan-A13B is an open-source large language model built on a Mixture-of-Experts architecture. It contains 80 billion total parameters but activates only 13 billion during inference, a design intended to balance model capability, computational efficiency, and deployment cost.

The model is pretrained on a rigorously filtered 20T-token corpus, with enhanced STEM data curation that improves factual reliability and reasoning ability. High-quality supervised fine-tuning and large-scale reinforcement learning further enhance its overall performance. Hunyuan-A13B also introduces a dual-mode Chain-of-Thought framework that adapts reasoning depth to task complexity: fast thinking for routine queries and slow thinking for complex, multi-step problems.

Evaluations show competitive performance across mathematics, science, programming, general language understanding, and agent tasks, often approaching that of much larger models. Its high inference throughput makes it suitable for latency-sensitive applications. The model is released to support open research and practical LLM deployment.