I have been having a lot of mixed mileage with Opus 5 on my different sessions. As always, like when I moved from 4.6 to 4.7 especially, it has immediately revealed all the gaps in my guarding and context management… On my best established sessions, the ones that are ‘steeped’ in client context and history, where the knowledge base is mature, it is GREAT - flying, not making any mistakes. It’s insanely good value, lower token spend than Fable and very deep working. On the less frequently visited sessions, it seems to be almost supernaturally good at finding any way it can to mess up. I’ve sworn at it more today than any previous session. I’ve had to send it back to check ‘facts’ 2, 3, 4 times in a row which I’ve never had to do. This morning, it found an edit to a file that was exactly an hour after its own edits, which it named as being made by one of my clients. I checked with my client, no edits - turned out it had forgotten that we are on UK time not UTC, found IT’S OWN edit and then blamed the client for zero reason. I’m also seeing all the things that people are complaining about - its personality is anxious, which makes ME anxious and nervous. The way it talks/writes is a definite step back, I’ve never had to ask Claude to explain what it means so much with any previous model, even having to ask it twice in a row. The most comical thing though is that as soon as it picks up on the fact that I have a holiday coming up, it’s literally obsessed with pushing work into the future because I won’t have time to develop it. MF you are going to do it in the next 20 minutes, like always. All in, a very frustrating mixed bag. It’s improving, but only because I’m having to go back to guards and basics with it again, like I did when moving from 4.6 > 4.7 (but not 4.7 > 4.8 OR to Fable.) Anyone else? submitted by /u/Danzarak
Originally posted by u/Danzarak on r/ClaudeCode