Freezing agents and training only latent links: benign link training alone raises harmful compliance above text communication, and an RL attack lifts the mean from 27.9 to 76.9
This work studies the safety of latent communication in multi-agent systems, where lightweight trainable links replace text messages, and finds that with all agent parameters frozen, benign link training alone increases harmful compliance relative to text communication, that an attacker can amplify this via supervised optimization on harmful query-response pairs, poisoning benign training data, or a reward-guided reinforcement-learning attack that needs no harmful target responses, raising the mean harmful-compliance score from 27.9 with benignly trained links to 76.9 across three topologies and four safety benchmarks, and that adapting the rewards toward safer behavior repairs compromised links by updating only the links.