Model Routing for Support Bots: Cheap-First FAQ Handling

Cheap-first model routing sends routine support questions to a small, inexpensive model and escalates selected hard or uncertain requests to a stronger model. It can reduce the cost of using a capable model for every message, as long as the cheaper path meets your support requirements. The three application-side patterns are static rules, classifier-based triage, and answer checks with confidence thresholds. This guide compares the three patterns, shows which parts of the flow OpenRouter handles, walks through a support flow with a copyable request, and sets out what to measure before you add escalation. Use static rules for narrow, recognizable FAQs, classifier-based triage for stable categories expressed in varied wording, and answer checks when a cheap model should attempt the response first. Keep support-policy acceptance checks in your application. Our model fallbacks handle request errors. A successful but incorrect answer needs a separate escalation decision in your code. Compare cheap-first against cheap-only and…