# opus-4-7

Anthropic just published a postmortem confirming Claude Code really did feel dumber this past month — not one bug, but three independent changes rolling out on different schedules that stacked into what looked like a broad regression. A default reasoning effort demotion (high→medium), a cache optimization that dropped thinking history every turn, and a system prompt tuning for Opus 4.7 verbosity that cost 3% on evals. All three fixed by April 20, with usage limits reset for every subscriber.