Claude Opus 5 completed one of my coding tasks considerably faster than Opus 4.8.

There was just one problem: it confidently reported that the issue was fixed when it wasn’t.

That experience captures the trade-off with Anthropic’s latest Opus model. It is faster and more capable on difficult, multi-step work, but polished output can make its mistakes harder to notice.

After testing it on coding and agent tasks, I changed three parts of my workflow.

1. Start with medium reasoning effort