GPT-6 Astra vs GPT-6.1 Sol vs Gemini 4 Argon vs Claude Fable 5.1: Which Frontier Model Fits Which Job

Anthropic, OpenAI, and Google DeepMind released four advanced AI models within a month: Claude Fable 5.1, GPT-6 Astra, GPT-6.1 Sol, and Gemini 4 Argon. OpenAI discontinued GPT-6.1 Astra due to internal issues, keeping GPT-6 Astra as its flagship. The models vary in pricing, access, and benchmark strengths across coding, finance, and software engineering tasks.