Are Multimodal LLMs Ready for Surveillance? A Reality Check on Zero-Shot Anomaly Detection in the Wild

In three linesSystematic evaluation of multimodal LLMs on video anomaly detection (VAD) using ShanghaiTech and CHAD benchmarks. Models exhibit conservative bias in zero-shot settings: high precision but recall collapse. Class-specific instructions improve F1-score from 0.09 to 0.64 on ShanghaiTech, yet recall remains a critical bottleneck for real-world surveillance.

Summary generated by Claude — human-verified