The price spread right now: open-weight models around $0.14 per million input tokens. Frontier flagships at $5.00. That's a 35x gap — and most pipelines send every request to the expensive one, because routing everything to the best model is the architecture you get when you don't make an architecture decision.
The fix is boring. Which is my favorite kind of fix.
Step one: classify the workload, not the model
Stop asking "which model is best?" and start asking "which tasks are cheap-safe?" The split is almost always the same:
High-volume, low-ambiguity — extraction, classification, formatting, summarization → cheap tier
