Model Routing Arbitrage

Model Routing Arbitrage treats the routing layer between your application and model providers as a margin instrument, not a plumbing detail. Every client request can be served by more than one model at more than one price, and the router decides which. Agencies that route on task complexity, latency tolerance, and cost per token keep retainer margins stable when a provider reprices or a model degrades. The frame matters because routing behavior is set at the model architecture level: mixture-of-experts systems select expert sub-networks per token, so output quality and inference cost shift with routing strategy before your prompt ever runs. A concrete case: an agency running a support-deflection build for a client can send classification calls to a cheap open model via Ollama or OpenRouter and reserve a frontier model for reasoning steps, cutting per-ticket spend without touching the deliverable. Gateways such as Helicone or Portkey make the switch a config change rather than a rewrite.