Gemini 3.6 Flash vs 3.5 Flash-Lite: API Migration Guide

Google released Gemini 3.6 Flash and 3.5 Flash-Lite as generally available API models. Use Gemini 3.6 Flash for coding and multimodal reasoning, and Gemini 3.5 Flash-Lite for extraction and high-volume subagent work. Remove incompatible fields and route by workload before changing a production default. Test both models with the same task fixtures and consider a fallback model.