Model routing needs policy, evals, and fallbacks

IBM Research's Hugging Face post argues that model routing is not just sending easy tasks to cheaper models; it requires task classification, fallback design, latency budgets, cost budgets, and evaluation. Why it matters: Routing can reduce spend only when reliability constraints are explicit. Without eval samples and fallback rules, a cheap-model router can quietly trade away quality or create hard-to-debug failures.

Try this: Before adding a router, write a one-page routing policy: task classes, acceptable quality loss, max latency, max cost, fallback model, and a small regression eval set.