Definition

Product architecture that dynamically or statically assigns user prompts to different underlying LLMs (in-house vs third-party, cheap vs frontier) based on task complexity, cost, latency, or policy.

Key Points

  • microsoft Excel/Outlook MAI routing (Jul 2026) is a high-volume cost example
  • Often opaque to end users (no model disclosure in Copilot UI)
  • Enables cheaper-default / premium-frontier pricing tiers

Sources