@article{thortoolintegratedhierarchicaloptimizati,
  title = {THOR: Tool-Integrated Hierarchical Optimization via RL for Mathematical Reasoning},
  author = {Qikai Chang and Zhenrong Zhang and Pengfei Hu and Jun Du and Jiefeng Ma and Yicheng Pan and Jianshu Zhang and Quan Liu and Jianqing Gao},
  year = {2025},
  eprint = {2509.13761},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2509.13761},
}