Google launches Gemini 4 Argon and Anthropic releases Claude Sonnet 5.5

Google has introduced the Gemini 4 Argon model, matching GPT-6 Astra on the Artificial Analysis Intelligence Index at 60% of the cost with a 15% hallucination rate. Meanwhile, Anthropic launched Claude Sonnet 5.5, scoring 56 on the same index with the highest output tokens per task seen.