Claude AI Revolution: An Up-to-Date 2025 Guide to Anthropic’s ChatGPT Rival
In May 2025, Anthropic released Claude 4 as Claude Sonnet 4 and Claude Opus 4, introducing a 200K+ token context window, code execution, and agentic tool use with a new Files API. Claude 2.1, released in November 2023, expanded the context to 200K tokens, cut hallucinations by about 2x, and added beta support for tool use such as API calls and web search. The Claude 3 family launched in March 2024 with Haiku, Sonnet, and Opus, added multimodal support (text and images) and a tiered model lineup, with Claude 3 Opus maintaining 200K context and experiments hinting at up to