Ya I've had this experience more than a few times recently. I've heard people claiming they are serving quantized models during high loads, but it happens in cursor as well so I don't think it's specific to Anthropics subscription. It could be that the context window has just gotten into a state that confuses the model... But that wouldn't explain why it appears to be temporary...

My best guess is this is the result of the companies running "experiments" to test changes. Or it's just all in my head :)

Cursor one is back to Claude 4 or 3.5+ at best. Struggles to do things it did effortlessly a few weeks ago.

It’s not under load either it’s just fully downgraded. Feels more they’re dialing in what they can get away with but are pushing it very far.