I am a PhD candidate in the School of Computing at National University of Singapore (NUS), advised by Prof. Bryan Hooi. Prior to that, I received my Master’s degree at Beijing University of Posts and Telecommunications, jointly advised by Prof. Chuan Shi and Prof. Xiao Wang. My research interests include Large Language Models, self-evolving Agents.

🔥 News

  • 2026.04:   Two accepted by ICML 2026
  • 2026.01:   One paper accepted by ICLR 2026

📝 Publications

Just-In-Time Reinforcement Learning: Continual Learning in LLM Agents Without Gradient Updates

Yibo Li, Zijie Lin, Ailin Deng, Xuan Zhang, Yufei He, Shuo Ji, Tri Cao, Bryan Hooi

ICML 2026 🌟 Spotlight (Top 2.2%)

Memory is Reconstructed, Not Retrieved: Graph Memory for LLM Agents

Shuo Ji, Yibo Li, Bryan Hooi

ICML 2026

APEX: Autonomous Policy Exploration for Self-Evolving LLM Agents

Yibo Li, Jiashuo Yang, Zhi Zheng, Zhiyuan Hu, Yuan Sui, Shizun Wang, Yufei He, Bryan Hooi

Preprint

WARD: Adversarially Robust Defense of Web Agents Against Prompt Injections

Tri Cao, Yulin Chen, Hieu Cao, Yibo Li, Khoi Le, Thong Nguyen, Yuexin Li, Yufei He, Yue Liu, Shuicheng Yan, Bryan Hooi

Preprint

TACT: Mitigating Overthinking and Overacting in Coding Agents via Activation Steering

Yuan Sui, Yulin Chen, Yibo Li, Xue Jiang, Yufei He, Yihong Dong, Xiaoxin He, Tianyu Gao, Bryan Hooi

Preprint

WebAgentGuard: A Reasoning-Driven Guard Model for Detecting Prompt Injection Attacks in Web Agents

Yulin Chen, Tri Cao, Haoran Li, Yue Liu, Yibo Li, Yufei He, Le Minh Khoi, Yangqiu Song, Shuicheng Yan, Bryan Hooi

Preprint

Learning to Learn-at-Test-Time: Language Agents with Learnable Adaptation Policies

Zhanzhi Lou, Hui Chen, Yibo Li, Qian Wang, Bryan Hooi

Preprint

Towards Realistic Personalization: Evaluating Long-Horizon Preference Following in Personalized User-LLM Interactions

Qianyun Guo, Yibo Li, Yue Liu, Bryan Hooi

Preprint

GuardReasoner-Omni: A Reasoning-based Multi-modal Guardrail for Text, Image, and Video

Zhenhao Zhu, Yue Liu, Yanpei Guo, Wenjie Qu, Cancan Chen, Yufei He, Yibo Li, Yulin Chen, Tianyi Wu, Huiying Xu, Xinzhong Zhu, Jiaheng Zhang

Preprint

EvoClinician: A Self-Evolving Agent for Multi-Turn Medical Diagnosis via Test-Time Evolutionary Learning

Yufei He, Juncheng Liu, Zhiyuan Hu, Yulin Chen, Yue Liu, Yuan Sui, Yibo Li, Nuo Chen, Jun Hu, Bryan Hooi, Xinxing Xu, Jiang Bian

Preprint

EvoTest: Evolutionary Test-Time Learning for Self-Improving Agentic Systems

Yufei He, Juncheng Liu, Yue Liu, Yibo Li, Tri Cao, Zhiyuan Hu, Xinxing Xu, Bryan Hooi

ICLR 2026

ConfTuner: Training Large Language Models to Express Their Confidence Verbally

Yibo Li, Miao Xiong, Jiaying Wu, Bryan Hooi

NeurIPS 2025

MLR-Bench: Evaluating AI Agents on Open-Ended Machine Learning Research

Hui Chen, Miao Xiong, Yujie Lu, Wei Han, Ailin Deng, Yufei He, Jiaying Wu, Yibo Li, Yue Liu, Bryan Hooi

NeurIPS 2025

AuCoGNN: Enhancing Graph Fairness Learning under Distribution Shifts with Automated Graph Generation

Xiao Wang, Yibo Li, Yujie Xing, Shaohua Fan, Chuan Shi

TKDE 2025

Advancing Molecular Graph-Text Pre-training via Fine-grained Alignment

Yibo Li, Yuan Fang, Mengmei Zhang, Chuan Shi

KDD 2025

Graph foundation models: Concepts, opportunities and challenges

Jiawei Liu, Cheng Yang, Zhiyuan Lu, Junze Chen, Yibo Li, Mengmei Zhang, Ting Bai, Yuan Fang, Lichao Sun, Philip S. Yu, Chuan Shi

TPAMI 2025

Graph Fairness Learning under Distribution Shifts

Yibo Li, Xiao Wang, Yujie Xing, Shaohua Fan, Ruijia Wang, Yaoqi Liu, Chuan Shi

WWW 2024

A Generalized Neural Diffusion Framework on Graphs

Yibo Li, Xiao Wang, Hongrui Liu, Chuan Shi

AAAI 2024

Less is More: on the Over-Globalizing Problem in Graph Transformers

Yujie Xing, Xiao Wang, Yibo Li, Hai Huang, Chuan Shi

ICML 2024 🗣️ Oral

Towards adaptive information fusion in graph convolutional networks

Meiqi Zhu, Xiao Wang, Chuan Shi, Yibo Li, Junping Du

TKDE 2023

Space4hgnn: A Novel, Modularized and Reproducible Platform to Evaluate Heterogeneous Graph Neural Network

Tianyu Zhao, Cheng Yang, Yibo Li, Quan Gan, Zhenyi Wang, Fengqi Liang, Huan Zhao, Yingxia Shao, Xiao Wang, Chuan Shi

SIGIR 2022

🎖 Honors and Awards

  • 2022.07 Outstanding Graduate Student Award of Beijing
  • 2023.10 The University’s First-Class Scholarship

📖 Educations

  • 2025.08 - now, PhD candidate in School of Computing, National University of Singapore, Singapore
  • 2022.09 - 2025.06, Postgraduate in the School of Computer Science, Beijing University of Posts and Telecommunications, Beijing, China
  • 2018.09 - 2022.06, Undergraduate in the School of Computer Science, Beijing University of Posts and Telecommunications, Beijing, China

💻 Internships

  • 2023.10 - 2024.03, Singapore Management University, Singapore