Model Routing

Simple Definition

Model routing is the practice of sending different parts of an AI workflow to different models based on cost, speed, quality, or task type.

Not every task needs your strongest model. A smart workflow may use one model for planning, another for execution, and another for review.

Why It Matters

Routing helps you spend expensive, high-quality models only where they add the most value, while cheaper or faster models handle the routine work. It can lower cost and reduce reliance on any single model.

Example

A developer uses Claude for planning, Codex for implementation, and Claude again for the final review — matching each model to the part of the job it does best.

Related Terms

• Model Fallback — routing to a backup when the main model fails
• AI Workflow — the multi-step process routing optimizes
• AI Automation — automated systems often route between models
• Reasoning Model — typically used for the planning and review steps
• AI Coding Agent — coding workflows are a common place to route work