The Model Writes, the Judge Measures: Anatomy of an LLM Judge

Here is the kind of sentence that should keep a team up at night: "At this clarity grade, you won't see a thing with the naked eye." Our assistant produced it while explaining a diamond. The grade it cites is real — SI1, printed on the stone's lab report. The promise attached to it is invented. A clarity grade is assigned under 10× magnification; it does not resolve what a naked eye will see. Two SI1 stones can look entirely different — one clean at arm's length, the other with a visible speck…