Prompt Engineering

Extended thinking isn’t just “model thinks longer”—it’s a fundamentally different interaction model. If you’re prompting extended thinking models (Claude Opus, o1) the same way you prompt standard models, you’re leaving most of the value on the table. This post is a developer’s mental model for working with these systems: when to use them, how to prompt them, and what trade-offs to expect. How Extended Thinking Actually Works Standard LLMs generate tokens one at a time, each token conditioned on everything before it. The model “thinks” only as fast as it speaks. Ask it to solve a complex problem, and it often commits to an approach in the first few tokens, then rationalizes that approach even if it’s wrong. ...

I’ve been skeptical of every “game-changing AI release” for the past two years. Every few months, a new model drops and Twitter explodes with claims that AGI is here. Spoiler: it never is. But when Anthropic released Opus 4.5, something actually shifted in how I work. Not because it’s AGI—it’s decidedly not—but because it’s the first model that consistently delivers on complex, multi-step reasoning without falling apart halfway through. ...