I've followed a few trackers, eg https://marginlab.ai/trackers/claude-code/ , for awhile. For Claude Code the trend, it seems to me at least, is fewer tokens to do the same or better job. Prompt changes, tool ergonomics changes, etc.; I'd be shocked if they didn't A/B every release. Less thinking as measured by tokens isn't necessarily bad if you can get the same results by making it think about the "right" things or structure. They obviously screw up sometimes, and I've always been suspicious with hidden tokens, but I haven't found evidence quality intentionally degrades over time.