Anthropic released Claude Fable 5.2 and Claude Mythos 5.2 on November 9. The models share an underlying system, with Fable available for general use and Mythos reserved for approved organizations. Anthropic says the update improves coding, reasoning and vision and can generate output up to 30% faster than the 5.1 versions.
What developers pay
Standard API pricing is $8 per million input tokens and $40 per million output tokens, down from $10 and $50. The optional fast mode doubles those rates to $16 for input and $80 for output. Anthropic says it can generate tokens up to 2.5 times as quickly. That measures output generation, while a longer task can also spend time using tools or waiting for external services.
Developers can select Fable 5.2 on the Claude Platform, Amazon Bedrock, Claude Platform on AWS, Claude Models on Google Cloud and Microsoft Foundry. Claude Code requires version 2.1.321 or later. Mythos is limited to approved organizations. Amazon Bedrock lists it for allow-listed organizations in AWS GovCloud (US). Fast mode is available through Claude Code, the Claude Platform, Claude Models on Google Cloud and Anthropic-hosted Microsoft Foundry. Only organizations in Anthropic’s verification programs can use fast mode with Mythos.
On Anthropic’s FrontierCode 2.0 coding evaluation, Fable 5.2 scored 49.1%, compared with 32.4% for Fable 5.1 at the same Xhigh effort setting. Anthropic continues to recommend Opus 5.5 for most everyday coding and knowledge work.
Anthropic applies 30-day retention for safety monitoring to customers without an eligible zero-data-retention arrangement. Its Enterprise Frontier Safeguards program, which lets safety monitoring run on data stored in the customer’s infrastructure, is in private beta.
What subscribers get
Pro subscribers and users with standard Team seats can spend up to half of their existing weekly allowance on any Fable model through November 16 at 11:59 p.m. Pacific time. Eligible users on those plans get one Fable reset that expires at the same time. Eligible Max and Ultra subscribers and premium seats on Team and legacy seat-based Enterprise plans get one to three resets based on paid subscription tenure. Those resets expire March 8, 2027 at 11:59 p.m. Pacific time.
A Fable reset restores weekly usage spent on Fable while leaving other weekly usage intact. Accounts with a five-hour limit also get that window refilled. Anthropic generally requires paid billing to have been in place before November 9 at 10 a.m. Pacific time for the resets. Team and Enterprise seat holders also needed to have joined by that cutoff. If Pro and standard Team users reach the 50% cap or the offer ends, further Fable use draws on usage credits if enabled.