🤖 Anthropic Introduces Claude Sonnet 5
The new model demonstrates performance on par with Opus 4.8 at a lower cost, supporting a 1 million token context window and up to 128,000 tokens of output.
🌍 The release confirms the trend of using Adaptive Thinking by default and optimizing tokenization approaches, which directly impacts API usage economics.
👤 When working via API, requests in English and code will effectively become ~30% more expensive due to the new tokenizer architecture, despite the existing price list.
Source 1: https://simonwillison.net/2026/Jun/30/claude-sonnet-5/