Claude Sonnet 4.5 System Card [pdf](assets.anthropic.com)
assets.anthropic.com
Claude Sonnet 4.5 System Card [pdf]
https://assets.anthropic.com/m/12f214efcc2f457a/original/Claude-Sonnet-4-5-System-Card.pdf
https://assets.anthropic.com/m/12f214efcc2f457a/original/Claude-Sonnet-4-5-System-Card.pdf
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...)