https://blog.yushi91.com/blog/anthropic/Recent content in Anthropic on Yushi's BlogHugoen-USCopyright © 2025, Yushi Cui.Thu, 09 Apr 2026 10:00:00 +1300https://blog.yushi91.com/blog/prompt-engineering-evaluation/Thu, 09 Apr 2026 10:00:00 +1300https://blog.yushi91.com/blog/prompt-engineering-evaluation/<p><img src="https://blog.yushi91.com/prompt-engineering-evaluation.webp" alt="Prompt engineering evaluation" loading="lazy"> </p> <h2 id="the-black-box-problem">The black box problem</h2> <p>Everyone knows prompts matter. You&rsquo;ve seen the Twitter threads. The Reddit posts. The &ldquo;here&rsquo;s my secret formula&rdquo; guides. I&rsquo;ve read most of them, and I actually learned from them. Step-by-step instructions instead of vague goals. A few examples so the model knows what you expect. A persona if it helps frame the task. These techniques are real and I use them daily.</p> <p>But I was always missing something: I had no idea if I was getting better.</p>