Claude Fable 5.1 Now in GitHub Copilot

How it developed

1. September 1, 2026GitHub ChangelogWhere it started

   Claude Fable 5.1 Now in GitHub Copilot

2. September 1, 2026TechCrunch AI

   Anthropic's Fable 5.1: Cheaper, Less Restrictive AI

   Fable 5.1 reduces token costs, eases restrictions, and offers zero data retention for on-premise use.

3. September 1, 2026The Verge AI

   Anthropic launches Claude Fable 5.1 with cost savings

4. September 1, 2026Wes Roth

   Anthropic releases Claude Fable 5.1 with cheaper caching

5. September 2, 2026The Rundown AI

   Anthropic launches Claude Fable 5.1 model

6. September 3, 2026Matt Wolfe

   Anthropic Introduces Claude Fable and Mythos 5.1

7. September 4, 2026AI Explained

   Anthropic Releases Fable 5.1 and Mythos Models