Prompt Engineering in 2026: The Complete Guide for Claude and GPT-4o Most people treat prompt engineering like a magic spell: tweak the wording, add “think step by step,” and hope for the best. That approach worked in 2023. In 2026, with Claude Sonnet 4 and GPT-4o handling genuinely complex multi-step tasks, sloppy prompting is the single biggest limiter on what these models can do for you. This guide covers the techniques that actually matter, with model-specific guidance for both Claude and GPT-4o. ...