Anthropic released Claude Fable 5.2 and Claude Mythos 5.2 on Monday, November 9 — two configurations of the same underlying model, and the company's most capable generally available models yet. Fable 5.2 carries safeguards that block most cybersecurity and biology requests, which is what lets Anthropic offer it broadly; Mythos 5.2 drops those blocks and is limited to organisations vetted through Anthropic's Cyber Verification Program or Life Sciences Verification Program. Fable is available now in Claude's paid plans, Claude Code, the Claude Platform (model ID claude-fable-5-2), and on AWS, Google Cloud and Microsoft Azure; Cognition made it available in Devin Desktop and Devin CLI on launch day.

The headline numbers: output up to 30 percent faster than the 5.1 generation, clearer communication, and a price cut — $8 per million input tokens and $40 per million output, down from $10/$50, with an optional fast mode at $16/$80 for up to 2.5x generation speed. Platform documentation lists a 1M-token context window and 128K maximum output. Anthropic says Fable 5.2 took the top spot on the Artificial Analysis Intelligence Index v5 at 65, and reports 49.1 percent on FrontierCode 2.0 at Xhigh effort, up from 32.4 percent for Fable 5.1. Paid-plan subscribers get extra Fable usage resets during launch week.

Anthropic still recommends most users start with Claude Opus 5.5 for everyday coding and knowledge work, moving to Fable or Mythos for the most ambitious, open-ended technical work. The launch is Anthropic's first frontier release since CEO Dario Amodei called in September for a slowdown in AI development, and it lands days ahead of the company's expected IPO marketing. Launch-day demos spread fast: Matthew Berman showed Fable 5.2 building a playable single-level Gears of War clone in Unreal Engine from a three-line prompt over a few days of unsupervised work. All benchmark and speed figures are Anthropic's own.