Claude Fable 5.2 reaches Foundry GA; Mythos access remains restricted
Microsoft introduced Claude Fable 5.2 and Fable 5.2 Fast as generally available models in Foundry, hosted on Anthropic.
The announcement describes technical work spanning software engineering, scientific analysis and finance, including extended investigation across repositories.
Claude Mythos 5.2 targets specialized security-engineering and life-sciences work, with access limited to authorized customers through Anthropic verification programs. Microsoft directs interested customers to their account team to confirm eligibility.
The announcement also describes safety-monitoring retention requirements and a temporary zero-data-retention option for eligible Fable customers until Enterprise Frontier Safeguards becomes available.
Partner briefing
- What it is
New Anthropic model availability in Microsoft Foundry.
- What’s changing
Fable5.2/Fast areGA; Mythos5.2 requires authorized access and verification.
- Why it matters
Distinguishes general availability from restricted models and applicable data-retention conditions.
- Who it affects
Developers and authorized organizations working on technical, security and scientific applications.