Anthropic releases Claude Fable 5.1 and Mythos 5.1
Fable 5.1 scores 55.8% on Terminal-Bench 4.0 in Claude Code, ahead of Fable 5 (42%) and Opus 5 (52.3%). Pricing matches Fable 5, but API cache reads drop 75% to $0.25/MTok; cyber-related fallbacks to Opus are down about 40%.
How this story unfolded
6 days · 28 reports · 89 community posts · 117 of 122 shown
- Sep 1
v2.1.257github.com
2.1.257code.claude.com
Introducing Claude Fable 5.1youtube.com
Anthropic Says New Fable 5.1 AI Model Is Cheaper, Better at Codingbloomberg.com
Anthropic's Claude Fable 5.1 and Mythos 5.1 arrive with a 75% cost reduction for Fable cache readsventurebeat.com
Claude Fable 5.1 now available on AI Gatewayvercel.com
Introducing Claude Fable 5.1 on AWSaws.amazon.com
Anthropic Ships Claude Fable 5.1, More Than Doubling Its Predecessor on Key Benchmarkdecrypt.co
Anthropic’s new Fable release is cheaper, less restrictivetechcrunch.com
Anthropic’s Fable 5.1 is a bit cheaper, a bit smarter, and refuses a lot lessthenewstack.io
Anthropic Releases Claude Fable 5.1 and Claude Mythos 5.1: 52.6% on Terminal-Bench-Science and 75% Cheaper Cache Readsmarktechpost.com
Anthropic launches Claude Fable 5.1 and says it’s up to 45 percent cheaper for agentic worktheverge.com
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