KAT-V1: Kwai-AutoThink Technical Report. - Zizheng Zhan; Ken Deng; Huaixi Tang; Wen Xiang; Kun Wu; Weihao Li; Wenqiang Zhu; Jingxuan Xu; Lecheng Huang; Zong-Xian Feng; Shaojie Wang; Shangpeng Yan; et al. (CoRR, 2025)