Claude 4 Opus is Anthropic’s flagship hybrid‑reasoning model that blends instant replies with optional step‑by‑step extended planning for deep multi‑step workflows. With SWE‑bench Verified scores near 72.5 % and sustained long‑task performance, it surpasses prior Opus and Sonnet versions in coding and agentic task execution. It shines at automating full‑stack code refactoring, running autonomous research agents, and streamlining client processes like proposal analysis or budgeting pipelines. You define a thinking budget to dial in reasoning depth, so you get exactly the right balance of speed and precision.