Post
Simon Willison
simonwillison.net
did:plc:kft6lu4trxowqmter2b6vg6z
I wrote some notes on what's new in the (published) Fable 5.1 system prompt in comparison to Fable 5 - it's mostly about not reproducing song lyrics and avoiding drawing copyrighted characters https://simonwillison.net/2026/Sep/2/claudes-new-system-prompt/
2026-09-02T14:18:49.404Z