README.md

June 17, 2026 · View on GitHub

ReactSim-Bench: Benchmarking Reactive Behavior World Model Simulation in Autonomous Driving

Paper | Data | Baselines

ReactSim-Bench is the first benchmark for systematicly evaluating the reactive capability of behavior world models in autonomous driving. It contains:

  • Reactive closed-loop protocol with decoupled control. In ReactSim-Bench, The behavior world model controls the surrounding agents, while the autonomous vehicle (AV) are controled by its own policy instead of the world model.
  • Customed AV behaviors beyond the log. ReactSim-Bench contains 2,636 scenarios with AV behaviors that differ from the log and create reactive pressure on surrounding agents. They are grouped into three categories: longitudinal,directional, and lateral deviations.
  • Safety and feasibility metrics. ReactSim-Bench evaluates Agent-AV safety, agent-agent safety, map compliance, driving-direction compliance, and kinematic feasibility.
  • Multiple baselines. We implement the Transformer-based (MTR), diffusion-based (CTG,VBD), and next-token-prediction-based (SMART, catk, Trajtok) behavior world models on ReactSim-Bench as baselines.

Usage

  1. Install the repository, download the data and preprocess: document.
  2. Setup the environment for each baseline and train or evalute:
  3. Follow the instruction to train and evaluate your own model on ReactSim-Bench

Dataset

ReactSim-Bench is built on nuPlan and contain 2636 test scenarios:

CategoryNumber of scenarios
Longitudinal deviation937
Directional deviation799
Lateral deviation900
Total2,636

The data is available at Hugging Face.

Benchmark

MethodA-AV Coll. CountA-AV risky CountA-A Coll. (%)Offroad (%)Direction violation (%)Acceleration infeasibility (%)Steering infeasibility (%)
Log Replay0.98291.53802.250.180.800.162.51
MTR0.14570.58193.292.672.830.6414.29
CTG0.61950.94764.882.952.1010.877.08
VBD0.22760.47113.191.032.350.010.18
SMART0.14190.39762.230.681.099.744.83
CATK0.14260.40292.220.691.1310.255.02
TrajTok0.14070.41732.230.611.033.233.93

The checkpoints of baselines are available at Hugging Face.

Citation

If you find ReactSim-Bench useful, pase cite:

@article{reactsimbench,
    title={ReactSim-Bench: Benchmarking Reactive Behavior World Model Simulation in Autonomous Driving}, 
    author={Zhiyuan Zhang and Yanlun Peng and Jianing Zhang and Xianda Guo and Zehan Huang and Haoran Liu and Qifeng Li and Shaofeng Zhang and Xiaosong Jia and Junchi Yan},
    year={2026},
    eprint={2606.14058},
    archivePrefix={arXiv},
    primaryClass={cs.RO},
}