collaborators

26 papers

cs.LG2026

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

Yibo Li, Zijie Lin, Ailin Deng +5

While Large Language Model (LLM) agents excel at general tasks, they inherently struggle with continual adaptation due to the frozen weights after deployment. Conventional reinforc…

cs.CR2026

AliMark: Enhancing Robustness of Sentence-Level Watermarking Against Text Paraphrasing

Yuexin Li, Wenjie Qu, Linyu Wu +5

Existing sentence-level watermarking methods enhance robustness to paraphrasing by anchoring watermarks in sentence semantics. However, their prefix-based designs remain vulnerable…

cs.CR2026

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

Zhenhao Zhu, Yue Liu, Yanpei Guo +9

We present GuardReasoner-Omni, a reasoning-based guardrail model designed to moderate text, image, video, and audio data. First, we construct a comprehensive training corpus compri…

cs.LG2026

APEX: Autonomous Policy Exploration for Self-Evolving LLM Agents

Yibo Li, Jiashuo Yang, Zhi Zheng +5

LLM agents have shown strong performance across a wide range of complex tasks, including interactive environments that require long-horizon decision making. But these agents cannot…

cs.CR2026

WARD: Adversarially Robust Defense of Web Agents Against Prompt Injections

Tri Cao, Yulin Chen, Hieu Cao +8

Web agents can autonomously complete online tasks by interacting with websites, but their exposure to open web environments makes them vulnerable to prompt injection attacks embedd…

cs.AI2026

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

Yuan Sui, Yulin Chen, Yibo Li +6

When language model agents tackle complex software engineering tasks, they often degrade over long trajectories, which we define as *agent drift*. We focus on two recurring failure…