👋 I am currently pursuing an M.S. in Computer Science at Northeastern University. My research interests include NLP, information retrieval, Retrieval-Augmented Generation, recommender systems, and multi-agent systems. You can find my publications on my Google Scholar profile Google Scholar citations: 99 .

🎓 I received my B.S. in Computer Science from Harbin Engineering University. My research is carried out at the NEU-ModelBest Data Intelligence Joint Lab, jointly established by Northeastern University and ModelBest, under the guidance of Associate Professor Zhenghao Liu. I also collaborate closely with Qiyuan Lab Qiyuan Lab, ModelBest ModelBest, and TsinghuaNLP TsinghuaNLP, and am mentored by Associate Researcher Yukun Yan.

· Last Updated: 2026-10-20 · hdxin2002@gmail.com

🔥 News

  • 2026.07:  🎉 We open-sourced StaffDeck OpenBMB/StaffDeck — Code Stars: 2.3k , an enterprise digital employee platform!
  • 2026.05:  🎉 We released PilotDeck OpenBMB/PilotDeck — Code Stars: 5k , a workspace-centric open-source agent operating system!
  • 2026.04:  🎉 Our paper MetaMem has been accepted at ACL 2026 (CCF-A)!
  • 2026.02:  🎉 Our paper Knowledge Intensive Agents has been accepted by AI Open (IF=14.8)!
  • 2026.01:  🎉 UltraRAG v3 OpenBMB/UltraRAG — Code Stars: 5.7k reached #2 on GitHub Trending!
  • 2026.01:  🎉 We released UltraRAG v3 OpenBMB/UltraRAG — Code Stars: 5.7k , making every step of the reasoning workflow visible!
  • 2025.11:  🎉 Our paper LISRec has been accepted at KDD 2026 (CCF-A)!
  • 2025.08:  🎉 Our paper LLMsPark has been accepted at EMNLP 2025 (CCF-B)!
  • 2024.04:  🎉 We released heu-icicles HEUOpenResource/heu-icicles — Code Stars: 428 , an HEU course guide and resource-sharing platform.
  • 2024.02:  🎉 Our paper MMAD has been accepted at COLING 2024 (CCF-B)!

🔨 Projects

GitHub Repo
StaffDeck project banner

StaffDeck: Enterprise Digital Employee Platform

ModelBest, NEU-ModelBest Data Intelligence Joint Lab, THUNLP, OpenBMB, and AI9Stars

Homepage: StaffDeck Docs: StaffDeck OpenBMB/StaffDeck — Code Stars: 2.3k

StaffDeck is an enterprise platform for building and managing digital employees. It turns professional experience, business processes, and decision criteria into digital employees that can work continuously, take over repetitive tasks, and preserve individual expertise as reusable, evolvable, and traceable organizational assets.

GitHub Repo
PilotDeck project banner

PilotDeck: A Workspace-Centric Open-Source Agent Operating System

THUNLP, ModelBest, OpenBMB, and AI9Stars

Homepage: PilotDeck Demo: Live OpenBMB/PilotDeck — Code Stars: 5k

PilotDeck is an open-source agent operating system built around workspace-level isolation, white-box memory, smart routing, and always-on background execution for long-running productivity tasks.

GitHub Repo
UltraRAG project logo

UltraRAG 3.0: No More “Blind-Box” Development — Every Line of Reasoning Made Explicit

THUNLP, NEU-ModelBest Data Intelligence Joint Lab, OpenBMB, and AI9Stars

Homepage: UltraRAG Docs: UltraRAG OpenBMB/UltraRAG — Code Stars: 5.7k

UltraRAG is a low-code MCP-based RAG framework that standardizes retrieval and generation components as MCP servers, with visual orchestration, evaluation, and demo deployment workflows.

📝 Publications

* indicates equal contribution, and † indicates corresponding author.

arXiv 2026
T²Mem framework: episode metadata and test-time memory construction

Test-Time Memory Construction

Zijun Wang*, Yifan Ji*, Haidong Xin, Zhenghao Liu†, Yukun Yan, Zulong Chen, Yu Gu, Ge Yu, Maosong Sun

arXiv: 2610.13348 OpenBMB/T2Mem — Code Stars: 5

T2Mem defers memory construction to inference, progressively retrieving episode metadata and raw interactions to build query-specific memory. It improves long-term dialogue question answering on LoCoMo and LongMemEval while reducing offline construction overhead.

ACL 2026
MetaMem paper figure

MetaMem: Evolving Meta-Memory for Knowledge Utilization through Self-Reflective Symbolic Optimization

Haidong Xin*, Xinze Li*, Zhenghao Liu†, Yukun Yan†, Shuo Wang, Cheng Yang, Yu Gu, Ge Yu, Maosong Sun

arXiv: 2602.11182 DOI: 10.18653/v1/2026.findings-acl.270 OpenBMB/MetaMem — Code Stars: 48

MetaMem is a meta-memory framework that keeps its memory evolving through self-reflective symbolic optimization, enabling more effective knowledge use across long-horizon human-LLM interactions.

KDD 2026
LISRec paper figure

LISRec: Modeling User Preferences with Learned Item Shortcuts for Sequential Recommendation

Haidong Xin, Zhenghao Liu†, Sen Mei, Yukun Yan, Shi Yu, Shuo Wang, Zulong Chen, Yu Gu, Ge Yu, Chenyan Xiong

arXiv: 2505.22130 DOI: 10.1145/3770854.3780337 NEUIR/LISRec — Code Stars: 18

LISRec strengthens sequential recommendation by learning personalized semantic shortcuts from user-item interaction histories, capturing stable user preferences more reliably.

AI Open
Knowledge Intensive Agents survey figure

Knowledge Intensive Agents

Zhenghao Liu, Pengcheng Huang, Zhipeng Xu, Xinze Li, Shuliang Liu, Chunyi Peng, Haidong Xin, Yukun Yan†, Shuo Wang, Xu Han, Zhiyuan Liu†, Maosong Sun†, Yu Gu, Ge Yu

DOI: 10.1016/j.aiopen.2026.02.002

A comprehensive survey of Retrieval-Augmented Generation from an agentic perspective: it organizes knowledge-intensive agents into knowledge-acquisition and knowledge-utilization roles, and outlines future directions for jointly optimizing multi-agent RAG systems.

WISA 2025
TASTE+ paper figure

Adapting Language Models to Text Matching based Recommendation Systems

Haidong Xin, Sen Mei, Zhenghao Liu†, Xiaohua Li, Minghe Yu, Yu Gu, Ge Yu

Hugging Face: Models DOI: 10.1007/978-981-95-6426-2_52 NEUIR/TASTE-plus — Code Stars: 4

By bringing language-model pretraining into recommendation, TASTE+ substantially improves the performance of text-matching-based recommendation.

EMNLP 2025
LLMsPark player agent architecture

LLMsPark: A Benchmark for Evaluating Large Language Models in Strategic Gaming Contexts

Junhao Chen, Jingbo Sun, Xiang Li, Haidong Xin, Yuhao Xue, Yibin Xu, Hao Zhao†

Homepage: LLMsPark arXiv: 2509.16610 DOI: 10.18653/v1/2025.findings-emnlp.12

LLMsPark is a game-theoretic benchmark for evaluating the strategic behavior and decision-making of large language models in multi-agent environments, offering a new lens on model intelligence.

COLING 2024
MMAD paper figure

MMAD: Multi-modal Movie Audio Description

Xiaojun Ye, Junhao Chen, Xiang Li, Haidong Xin, Chao Li, Sheng Zhou†, Jiajun Bu

Homepage: MMAD DOI: 10.63317/4s5pfq3wxzuq Daria8976/MMAD — Code Stars: 17

MMAD advances multi-modal movie audio description, bringing a richer movie-watching experience to people who are blind or have low vision.

ArXiv 2026
MemShot paper figure

Memory Shot for Long-Term Dialogue

Chunyi Peng*, Haidong Xin*, Xuanshuo Sheng, Xin Dai, Zhenghao Liu†, Shuo Wang, Yukun Yan, Zulong Chen, Yu Gu, Ge Yu

arXiv: 2606.28338 Hugging Face: Dataset NEUIR/MemShot — Code Stars: 5

MemShot renders dialogue spans into structured visual memory units and uses the model’s visual reasoning to link key episodes, making long-term dialogue memory construction up to 70x faster.

ICIC 2026
CAGMamba paper figure

CAGMamba: Context-Aware Gated Cross-Modal Mamba Network for Multimodal Sentiment Analysis

Minghai Jiao, Jing Xiao†, Peng Xiao, Ende Zhang, Shuang Kan, Wenyan Jiang, Jinyao Li, Yixian Liu, Haidong Xin

arXiv: 2604.03650 DOI: 10.1007/978-981-92-3417-2_26 User2024-xj/CAGMamba — Code Stars: 5

CAGMamba is a context-aware gated cross-modal Mamba network for multimodal sentiment analysis that models dialogue-level sentiment evolution and adaptively balances cross-modal fusion against modality-specific cues.

ArXiv 2026
SEEK paper figure

SEEK: Steering LLM Reasoning for RAG via Internal Reasoning Sketches

Xinze Li, Yuqing Lan, Zhenghao Liu†, Haidong Xin, Yukun Yan†, Shuo Wang, Zheni Zeng, Sen Mei, Ge Yu, Maosong Sun

arXiv: 2601.09402 OpenBMB/PAGER — Code Stars: 6

SEEK steers LLM reasoning for RAG with internal reasoning sketches that guide iterative retrieval, organize knowledge along multiple dimensions, and lead to more accurate answers.

MCM/ICM 2023
MCM/ICM paper figure

Puzzle Game: Prediction and Classification of Wordle Solution Words

Haidong Xin*†, Fang Wu*, Zhitong Zhou*

arXiv: 2403.19433

A detailed quantitative study of the Wordle game that uncovers the statistical patterns behind its solution words.

🏆 Awards

  • 2025.11 🥇 First-Class Excellent Student Scholarship.
  • 2024.11 🥇 First-Class Excellent Student Scholarship.
  • 2023.07 🥈 National Second Prize, Chinese Collegiate Computing Competition (4C 2023).
  • 2022.11 🥇 First Prize, China Undergraduate Mathematical Contest in Modeling (CUMCM 2022).
  • 2022.10 🥈 Second Prize, Mathematical Modeling Competition of the Three Northeastern Provinces.
  • 2022.05 🥇 First-Class Excellent Student Scholarship.
  • 2021.05 🥇 First-Class Excellent Student Scholarship.

📖 Education

💬 Media Mentions

💻 Research and Internships

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