Claude Opus 4.8 ships with honesty gains, effort controls, and one very expensive lesson

From the editor

The throughline today is capability outpacing intuition. Opus 4.8 lands with real improvements: fewer hallucinations, better agentic safety, effort controls. But the community immediately learned that effort controls can spawn 45 agents without warning, and one developer burned a billion tokens in a month. The pattern is consistent: each new lever Anthropic ships creates new ways to overspend, over-scale, or misfire. The tooling is maturing fast. User judgment is lagging behind. That gap is today's real story.