Claude Fable 5.2 launches for less. Mythos 5.2 checks the guest list.

That “up to” isn’t decorative. This is an output-generation claim, not a guarantee that every coding project will finish 30% sooner. Source

Big projects, not every project

Anthropic says Fable 5.2 can coordinate teams of AI agents and tackle long-running software projects. The company says agents running an earlier version migrated a critical production service from Python to Rust, and that the service now starts about 26 times faster. Source Source

That multiplier belongs to the service’s startup time, not Claude’s output speed; the numbers don’t get to swap name tags. The launch reports from The Verge and 9to5Mac don’t include independent verification of those figures. Source Source

For most coding and knowledge tasks, Anthropic still recommends starting with Opus 5.5, then switching models according to the work’s scope and complexity. Fable and Mythos are its recommendation for more ambitious, open-ended technical work. Source

A new-model announcement that tells you not to use the new model for everything? Keep that part.