Custom reward functions for multi-turn reinforcement learning with Amazon Nova Forge
Amazon Nova Forge enables custom reward functions for multi-turn reinforcement learning via BYOO capability
“A subtly wrong reward can quietly teach the wrong thing while every training curve looks healthy.”
AWS launched general availability of serverless multi-turn RL on Amazon Nova Forge, with a technical deep-dive on designing composite reward functions using GRPO. The post highlights a key pitfall where the highest-weighted reward component can silently contribute zero learning signal despite healthy-looking training curves. This is an engineering-level signal relevant to teams doing agentic model fine-tuning, but is AWS-platform-specific rather than a broad industry shift.