What Is Nemotron 3.5 Lightning

Nemotron 3.5 Lightning is NVIDIA’s open-weight 30B mixture-of-experts model with about 3B active parameters per token, built for the high-volume execution calls in an agent run. This post covers what the architecture means, how the model compares with Nemotron 3 Ultra, what context and features each OpenRouter endpoint exposes, and how to call it with structured outputs.