How do you troubleshoot over-verification behavior in a Claude Opus 5 agentic workflow?

Start by auditing the prompt for verification instructions carried over from an Opus 4.8 setup - a blanket "double-check your work" or similar global instruction is the most common source, since it compounds with Opus 5's stronger built-in self-verification rather than adding proportional value.

Check whether the extra verification is showing up as genuinely repeated re-checking of the same work, versus the model simply producing a somewhat longer response by default, since these are related but distinguishable symptoms - Opus 5's baseline verbosity is also higher than Opus 4.8's, and it's worth isolating which effect is actually driving the token cost you're trying to reduce.

If a global verification instruction is confirmed as the cause, remove it, and instead scope any remaining explicit verification instruction narrowly to the specific step or steps where a mistake would be especially costly, rather than applying it across the whole task.

Validate the fix by comparing token usage and output quality before and after the change on your own evaluation set, since the goal is confirming that removing the blanket instruction reduces cost without meaningfully regressing correctness on the steps that matter, not just assuming the fix worked based on the prompting guidance alone.