The model is a committee with a slug

Two models disagree about your codebase often enough that you ask both. The agent settings make that a model in its own right.

PUT /api/v1/agent/settings/fusion/balanced-ensemble stores a composite: a name, a method such as weighted-vote, members: one model at weight 0.6, another at 0.4: and a context window. The daemon validates it server-side: the members, no cycles, a non-zero window. The slug derives from the name; the path can't rename what the body describes.

From then on fusion/balanced-ensemble sits in the model catalogue beside the provider models, tagged source: "fusion", and a session switches to it like any single model. Each member's tokens bill by its own path: gateway at provider cost plus 5% from AI Balance, or your own provider key. A composite that fails validation still lists under ?include_invalid=true with its reason, editable rather than lost.

Nobody wrote an orchestrator. The ensemble is a row in settings, addressed like a model.