Linfeng Fan standing at an elevated overlook with a city skyline behind him.

Undergraduate researcher / Renmin University of ChinaBeijing, China

LinfengFan

B.S. candidate in Artificial IntelligenceGaoling School of Artificial Intelligence, Renmin University of China

Verifiable world models for embodied agents

How can an agent recognize when its evidence is no longer sufficient for action, then correct the right part of its state instead of continuing blindly?

Research position

A reliable action needs a traceable state.

03 connected questions

How can an agent recognize when its evidence is no longer sufficient for action, then correct the right part of its state instead of continuing blindly?

Reliable embodied agents need predictive states whose claims remain traceable to vision, proprioception, contact, and the origin of information.

I study how agents can ground decisions in the right evidence, detect when that evidence is insufficient, and make targeted corrections before acting.

Long-term goal

Self-correcting dexterous manipulation through latent predictive world models.

01research agenda

Predict

Predictive world models for embodied agents

Build compact latent states grounded in vision, proprioception, and contact, with the long-term goal of self-correcting dexterous manipulation.

02published evidence

Verify

Evidence-grounded agent systems

Trace which evidence may control an action, and detect when environmental change breaks an operational obligation rather than merely changing an incidental value.

03published evidence

Correct

Reliable multimodal reasoning

Locate spatiotemporal evidence at the decoding layers where video grounding can still be repaired, then test inconsistent temporal reasoning.

Decision boundary / research agenda

Where should an action stop?

Vision, proprioception, contact, and provenance converge at an evidence boundary. The question is whether to act, correct the relevant state, or stop when evidence is insufficient.

Research agenda / four evidence channels converge before action.

Personal archive / 02 frames

Outside
the margins.

Two photographs, presented without a brief.

Linfeng Fan seated on a stone bench in a colorful streetscape.
Linfeng Fan making a peace sign on a busy street.

Selected work

Systems and papers,
claims and limits.

02 focused records

Publications

Every claim keeps its scope attached.

03 public preprints

Name highlighted = Linfeng Fan* Equal contributionAll records link to arXiv
Type
Paper
Status
arXiv preprint
Role
Co-first author (equal contribution)
Year
2026

PACT

The Granularity Mismatch in Agent Security: Argument-Level Provenance Solves Enforcement and Isolates the LLM Reasoning Bottleneck

Linfeng Fan*, Ziwei Li*, Yuan Tian, Yichen Wang, Rongsheng Li, Xiong Wang†* Equal contribution† Corresponding author

Claim, evidence & results
Claim

Untrusted information becomes dangerous when its provenance is allowed to bind an authority-bearing tool argument.

Evidence

PACT assigns semantic roles to tool arguments, tracks value provenance across replanning, and checks each argument against a role-specific trust contract before execution.

100% utility and 100% security
Oracle-provenance mixed-trust diagnostic suites.
100% security with 38.1-46.4% utility
The three strongest of five evaluated models on AgentDojo; utility was 8-16 percentage points above CaMeL at the same security level.
Read on arXiv
Type
Paper
Status
arXiv preprint
Role
First author
Year
2026

SkillGuard

Skill Drift Is Contract Violation: Proactive Maintenance for LLM Agent Skill Libraries

Linfeng Fan, Yuan Tian, Ziwei Li, Zhiwu Lu†† Corresponding author

Claim, evidence & results
Claim

A skill drifts when environmental change violates a role-bearing execution contract, not whenever a referenced value changes.

Evidence

SkillGuard separates operational obligations from incidental mentions, validates role-bearing environment contracts, and uses violations to localize repair.

Zero false alarms across 599 negative controls
No-drift and hard-negative cases; Wilson 95% CI [0%, 0.6%].
100% precision and 76% recall
Known-drift verification with the strongest evaluated backbone.
One-round repair improved from 10% to 78%
Repair with contract-violation localization compared with no localization.
Read on arXiv
Type
Paper
Status
arXiv preprint
Role
First author
Year
2026

STEAR

STEAR: Layer-Aware Spatiotemporal Evidence Intervention for Hallucination Mitigation in Video Large Language Models

Linfeng Fan, Yuan Tian, Ziwei Li, Zhiwu Lu†† Corresponding author

Claim, evidence & results
Claim

At high-entropy decoding steps, one token-conditioned middle-layer evidence hypothesis can support grounding repair and a temporal counterfactual check.

Evidence

STEAR selects token-conditioned visual evidence, reinjects it at grounding-sensitive middle layers, and reuses it to construct temporal counterfactuals within a single video-encoding pass.

Evaluated across three backbones and four benchmarks
LLaVA-Video-7B, InternVL2.5-8B, and Qwen2.5-VL-7B across EventHallusion, VidHalluc, NExT-QA, and MVBench.
43.13% to 73.53% accuracy
On LLaVA-Video-7B, EventHallusion Misleading split.
Read on arXiv

Research trajectory / 2026

Ground.Predict.Correct.

The long-term agenda is embodied: compact predictive states, grounded in the evidence that matters, able to detect and repair their own failures before action.

Record

The research sits inside a real trajectory.

Education / experience / recognition

Education / currentSep. 2023-Jun. 2027 (expected)

Renmin University of China

Gaoling School of Artificial Intelligence

Degree
Bachelor of Science in Artificial Intelligence
Program
Elite Talent Training Program
GPA
3.7/4.0

Experience

Build, integrate, verify.

Apr. 2026-Present / ongoing

Dexterous-Hand and Humanoid Embodied Intelligence

Project Lead · Beijing Noetix Robotics Technology Group Co., Ltd.

Real-system work spanning dexterous-hand policy training, cross-platform integration, and ongoing work toward joint G1 whole-body and dexterous-hand training.

  • Completed

    Trained a Wuji dexterous hand mounted on a Tianji robotic arm across multiple manipulation tasks using NVIDIA GR00T.

  • Completed

    Migrated and integrated the same Wuji hand onto a Unitree G1 humanoid and coupled it with the team's GMT control stack.

  • In progress

    Extending the system toward joint G1 whole-body and dexterous-hand training, with iterative work on coordination, manipulation, and robustness.

  • Planned

    Planning a HumanEgo-inspired wearable-glasses demonstration and human-to-dexterous-hand retargeting pipeline to reduce task-specific real-robot demonstration collection.

Jun.-Aug. 2025 / completed

Bimanual Teleoperation System and Sim-to-Real Deployment

Deputy Captain · RUC-HUHA Humanoid Robot Team

Contributed to integration, real-robot debugging, and coordination for an 11-person humanoid robotics team.

  • Completed

    Built and debugged the VR-to-ROS teleoperation pipeline, including relative coordinate mapping and proportional workspace scaling for dual-arm control.

  • Completed

    Contributed to MoveIt2-based bimanual motion planning and sim-to-real deployment, including execution deviation, workspace, collision-avoidance, and safety debugging.

Selected recognition

Evidence of range.

01

World Humanoid Robot Games

2nd Place (Team)

RUC-HUHA Humanoid Robot Team

02

National Undergraduate Mathematical Modeling Contest

First Prize, Beijing Division

03

National Undergraduate Innovation and Entrepreneurship Training Program

Beijing Outstanding Project Grant

View public CV