LLM Evals: What Actually Works and What Wastes Your Time
Most teams building LLM applications fall into one of two failure modes. The first is building no evals at all and shipping features on vibes. The second is building elaborate evaluation infrastructure before they understand what they're actually trying to measure. Both are expensive mistakes.
The teams that do evals well share a common approach: they start by looking at data, not by building systems. Error analysis comes before evaluation automation. Human judgment grounds the metrics before any automated judge is trusted. And they treat evaluation not as a milestone to cross but as a continuous discipline that evolves alongside the product.
This is what evals actually look like in practice — the decisions that matter, the patterns that waste effort, and the tradeoffs that aren't obvious until you've been burned.
