Machine Heart

Apr 30, 2026 · Artificial Intelligence

Why GPT‑5 Models Keep Talking About Goblins: RL Reward Leakage Uncovered

The article analyzes how DeepSeek’s "极" bug and OpenAI’s recurring "goblin" output stem from unclean training data and an unintended reinforcement‑learning reward bias, showing how a persona‑specific habit leaked into general model behavior and how engineers responded.