I wasn't aware of the setting - I changed it to "Concise" now, thanks.

Opus 5 was in another league. But often Opus 5.5 still has its moments.

I was informing it of a bug and it started its lengthy response with: "I confirmed less than I claimed" as if I had just accused it of being wrong or otherwise complained.

I found that one weird, and it reminded me that I am talking to Claude rather than an OpenAI model.