
simonwillison.net
September 2, 2026
5 min read
44/100
Summary
Claude Fable 5.1 made me a really nice animated pelican 1st September 2026 Today is Claude Fable (and Mythos) 5.1 day. Anthropic say that Fable 5.1 “sets a new standard for coding, knowledge work, and long-running problem-solving tasks”. Their announcement spends a notable amount of time on scientific research, boasting of a 52.6% score on the brand new Terminal-Bench-Science 0.1 benchmark (first ...