AvaTaR: Optimizing LLM Agents for Tool Usage via Contrastive Reasoning - Wu, Shirley; Zhao, Shiyu; Huang, Qian; Huang, Kexin; Yasunaga, Michihiro; Cao, Kaidi; Ioannidis, Vassilis N.; Subbian, Karthik; Leskovec, Jure; Zou, James (Advances in Neural Information Processing Systems, 2024)