Claude Sonnet 4.5 System Card [pdf]

[synthwave]

https://assets.anthropic.com/m/12f214efcc2f457a/original/Claude-Sonnet-4-5-System-Card.pdf

[dang]

Comments moved to https://news.ycombinator.com/item?id=45415962, which was posted a bit earlier.

We'll put the system card link in the toptext there too.

(Sorry synthwave! - it's on our list to implement a karma sharing system for cases like this so multiple submitters can get the 'credit' for a post...)