Anthropic's model line for agentic coding, long refactors, and knowledge work that spans many steps - with a 1M-token context window.
Claude Fable is a newer model line from Anthropic, introduced in 2026 alongside the familiar Opus, Sonnet, and Haiku models. It is tuned for work that runs over many steps: agentic coding, long code refactors, multi-stage workflows, and knowledge work such as research and document preparation.
The latest version, Claude Fable 5.1, was released in September 2026 and improves on Fable 5 across the board, with the biggest gains in agentic coding, long-running workflows, and front-end and visual work. Like other current Claude models, it accepts text, images, and files and has a context window of 1 million tokens.
Claude Fable is a newer Anthropic model line tuned for long-running agentic coding and knowledge work.
Opus is Anthropic's flagship for the most demanding reasoning, and Sonnet is built for well-scoped everyday work. Fable focuses on long, multi-step workflows such as large refactors and front-end work.
Claude Fable 5.1, released in September 2026.
Claude Fable supports a context window of 1 million tokens.
Yes, the Claude chat on chatai.org is free and requires no registration. There is a daily message limit.
Yes. Claude Fable accepts text, images, and files as input.