Routing decision belongs in the agent harness
The routing decision belongs in the agent harness—not a generic gateway—because choosing the right model requires domain and task context that the harness already assembles and that a gateway typically lacks.
Supporting evidence
How to Build a Model Router in the Harness
Original excerpt
We believe that routing decision belongs in the agent harness , not a generic gateway, because choosing the right model requires the same domain and task context the harness already assembles and that a gateway typically lacks.
Context
Past a certain point, you hit diminishing returns: a more capable model adds little quality while cost and latency keep climbing. A good agent has model-harness-task fit : the right model with the right context for a given task. A model router picks that model for each task.