Write better with Claude Fable 5.1

Writing is most of what people ask Claude for, and Anthropic's prompting guide for Claude Fable 5.1 describes one problem with its prose. It can be dense, with long sentences and few paragraph breaks. In this short hands-on lab you write with the real model, see that problem on an everyday request, add the instruction Anthropic recommends, and measure the difference with a small script. Three lessons, from a first draft to a reusable style file for your own writing, for beginners and experienced Claude users alike.

Last updated: September 2026