So, I did some research. The regression is real. But it's not Claude getting dumber. And you can fix that. Thinking budgets were adjusted. For complex multi-file work, the default medium effort may not be enough. Three fixes: 1. /effort high (or /effort max on Opus for hard debugging) 2. ~/.claude/settings.json → "showThinkingSummaries": true 3. CLAUDE.md: "Research the codebase before editing. Never change code you haven't read." GitHub issue #42796 analyzed 17,871 thinking blocks across 6,852 sessions. The pattern: when thinking depth drops, the model shifts from research-first to edit-first. Claude didn't get worse. The defaults got conservative.

Mistakes happen. As a team, the important thing is to recognize it’s never an individuals’s fault — it’s the process, the culture, or the infra. In this case, there was a manual deploy step that should have been better automated. Our team has made a few improvements to the automation for next time, a couple more on the way.