Anthropic launched Claude Fable 5.1 and cyber/life-science Mythos 5.1, calling them the world’s most advanced models for coding and knowledge work. Fable 5.1 scores 55.8% on Terminal-Bench 4.0 (vs 42.0% for Fable 5) and 52.6% on Terminal-Bench-Science 0.1—more than double its predecessor—while cache reads cost 75% less, cutting typical bills ~25% and highly agentic ones up to 45%.
Key Takeaways
- ✓Fable 5.1 is available everywhere today; Mythos 5.1 is trusted-access only
- ✓55.8% on Terminal-Bench 4.0 and 52.6% on Terminal-Bench-Science 0.1
- ✓75% cheaper cache reads; up to 45% lower cost on highly agentic workloads