Just curious how the router decides on which model to use. When I use Claude Code, I often ask Claude Code to decide itself if it should spawn a sub-agent to downgrade or upgrade the model. Claude Code is smart to know how much context and cache it has and will decide if it should use sub-agent with a lesser model (sometimes it costs more to re-fetch tokens with a Sonnet sub-agent if the parent agent already has the context).
We trained a model to select which LLM to call at any given turn, based on lots of agent traces