Getting the most out of Opus 5.5 in Claude and Claude Code

Opus 5.5 is Claude's latest model that works longer on complex, multi-step tasks with minimal oversight—key improvements include always thinking before replying and maintaining context throughout extended runs. The guide recommends prompting Opus 5.5 by clearly defining what "done" looks like, removing redundant "think carefully" instructions, and providing complete tasks upfront rather than step-by-step directions. Users can also add follow-up instructions mid-task to steer long runs and should specify design preferences to avoid generic outputs.