As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/p/x-felixrieseberg-2119867837296857361/

# “We’re releasing Claude Fable & Mythos 5.2!”

Felix Rieseberg (@felixrieseberg), X, 2026-11-09.
Source: https://x.com/felixrieseberg/status/2119867837296857361

## Archived text

> We're releasing Claude Fable & Mythos 5.2! They're good models, I have some demos and tips for you.
> 
> Fable beats Opus on big, long tasks. Good examples are rewriting an entire codebase, creating an excellent first draft of a large artifact, or exploring ambiguous scenarios.
> 
> I expect to see it used to port a lot of stuff to Rust, support journalists in large-scale investigations, and help with research & science. I often still prefer Opus 5.5 for everyday work. Fable's got a big brain and thinks a little slower.

Archived 2026-11-10 via fxtwitter (unofficial).
Counts: 83,966 views, 1,454 likes, 78 reposts, 63 replies (at fetch time)
Media: https://pbs.twimg.com/media/HWtGmDiaUAA85Hz.jpg?name=orig

## Cited in

- 2026-11-09: [Anthropic releases Claude Fable 5.2 and Claude Mythos 5.2](https://postcutoff.com/e/2026-11-09-claude-fable-5-2-mythos-5-2/)