Claude Fable 5 / Mythos 5 — The strongest AI suddenly disabled worldwide 🔥
Anthropic released Claude Fable 5 (Mythos-class) on June 9, but it was abruptly disabled for all international users just days later due to U.S. government export control directives.
Right after launch, it dominated almost every major benchmark, especially in Agentic Coding.
[Key Benchmark Highlights (Claude Mythos 5 / Fable 5)]
- SWE-Bench Pro: 80.3% (Opus 4.8: 69.2%, GPT-5.5: 58.6%)
- FrontierCode (Diamond, xhigh): 29.3% (Opus 4.8: 13.4%, GPT-5.5: 5.7%)
- Strong leads in Knowledge Work, Spatial Reasoning, Tool Use, Cybersecurity, Health, and more.
The performance gap is massive — see the attached charts.
It’s a shame. This model was clearly a huge leap, especially in real agentic workflows and hard coding tasks.
The U.S. government’s national security concerns apparently forced this quick global shutdown.
AI progress vs. global regulation tension is getting real. Attention is now shifting heavily to Grok, GPT-5.5, and others.
What do you think? Anyone got to try Fable 5 before it was cut off?
#Claude #Fable5 #Mythos5 #AI #AgenticCoding #SWEbench
I was shocked by the quality of the chip design files analyzed by Sonet 4.6 today.
How good are Fable 5 and Mythos 5, which are being banned by the US government?