Gemini 3.8 Flash vs Claude Fable 5.1 vs GPT-5.6 Sol: which API should developers use?

Google released Gemini 3.8 Flash on September 2, 2026, maintaining a price of $0.75 per million input and $3.75 per million output tokens. While speed and a one-million token context remain similar to Gemini 3.7 Flash, the model now utilizes shorter reasoning steps and iterative tool calls. Although benchmark scores have increased, tasks may consume more tokens. On the Artificial Analysis Intelligence Index, Gemini 3.8 Flash scores 59, matching GPT-5.6 Sol and exceeding Claude Fable 5.1.