Release2026-09-01
Anthropic released Claude Fable 5.1, its most capable generally available model for coding and complex knowledge work. It is available to Pro, Max, Team and Enterprise subscribers and through the Claude API, Amazon Web Services, Google Cloud and Microsoft Foundry. Use requires 30-day data retention by default, and questions touching biology or cybersecurity are automatically answered by weaker Opus models instead.
What changed
Fable 5 was the top model, with cache reads priced four times higher.
What it unlocks
Running long, hours-long automated work sessions at a much lower cost per task, including workloads previously kept on Opus.
- $10/M input, $50/M output tokens
- cache reads $0.25/M, 75% less
- ~25% cheaper typical workloads
- US-only inference at 1.1x price
What you need to act on it
- a Pro, Max, Team or Enterprise plan, or API access
- 30-day data retention accepted by default
Sources