Anthropic has released Claude 3.5 Sonnet, a new AI model that outperforms its predecessor and competitor models in various evaluations, with improved speed and cost-effectiveness. The model is available for free on Claude.ai and the Claude iOS app, with higher rate limits for subscribers. Claude 3.5 Sonnet has shown significant improvements in graduate-level reasoning, undergraduate-level knowledge, and coding proficiency. It also introduces a new feature called Artifacts, which allows users to interact with Claude in a more dynamic workspace.