Anthropic's AI coding assistant that runs as a command-line tool directly in your terminal — reading code, executing commands, committing Git changes. Not just an AI that writes code, but an AI Agent that can take autonomous actions inside your development environment.

The fastest and least expensive model in the Claude lineup. Built for high-volume simple tasks — translation, classification, format conversion, quick Q&A. Use it when you need to handle hundreds of requests per second, or when the task is simple enough that you don't need "smart."

The flagship of the Claude lineup and Anthropic's most capable model at any given time. Built for tasks that require deep reasoning, complex analysis, or high accuracy requirements — use it when the cost of being wrong is high.

The workhorse of the Claude lineup, hitting the sweet spot between capability and speed. The default choice for most everyday tasks — capable enough, fast enough, reasonably priced, and currently the default model on Claude.ai.