GitHub made Copilot Fusion generally available on October 28 . The short version: when you pick Fusion in the model picker, you are no longer picking a model. You are picking an effort level, and a runtime router decides which model or models serve each step of your task. GitHub told VentureBeat plainly: "It's not a model. It's an orchestration engine at runtime."

That is a bigger interface change than it sounds, and it landed with a benchmark claim worth reading carefully, an admin policy surface worth configuring on day one, and a local-model preview with a cloud footnote nobody should miss.

What actually shipped on October 28

Fusion merges two earlier GitHub systems: Project HydraFusion, the multi-model orchestration research preview, and Copilot's automatic model selection.…