https://magnus919.com/tags/model-selection/Recent content in Model Selection on Notes from the Rabbit HoleHugoen© [Magnus Hedemark](https://github.com/magnus919)Sun, 02 Aug 2026 00:31:37 -0400https://magnus919.com/2026/08/stop-using-your-middle-model-by-default/Sun, 02 Aug 2026 00:31:37 -0400https://magnus919.com/2026/08/stop-using-your-middle-model-by-default/<p>The cheapest AI model isn&rsquo;t the one with the lowest token price. It&rsquo;s the one that gets acceptable work across the finish line with the fewest retries, repairs, and wasted minutes.</p> <p>That sounds obvious, but it is not how most of us pick models. When a model family has a cheap tier, an expensive tier, and a middle tier, the middle feels responsible. It sounds like the sensible default.</p> <p>OpenAI&rsquo;s <a href="https://openai.com/index/advancing-the-price-performance-frontier-with-gpt-5-6/">GPT-5.6 family</a> makes this temptation easy to see. Sol is the frontier model. Terra is the middle. Luna is the inexpensive, high-volume option. A reasonable first instinct is to use Terra most of the time, move up to Sol when the work looks hard, and drop to Luna when it looks trivial.</p>