Cost and latency in model-based systems
Lowering cost
Attach less context; route simple requests to a small model; exploit caching for fixed parts; and batch what isn't urgent.
Compute cost per business unit — per request, per user, per order — not just a monthly sum. That's how you see whether growth pays off.
Speeding up
Streaming the answer to the user shortens the perceived wait more than any other optimization. Shortening the output length helps directly. And tasks that can run in parallel — run in parallel.
Protecting the budget
Daily caps, alerts on threshold crossings, and a step limit in automated processes. A wrong loop can burn a monthly budget in hours.
Going deeper
Tag every call by user, capability and purpose. Without tagging, the question “what caused the spike” is answered by guessing, and you can't turn off the expensive, less-useful capability — which almost always exists and only surfaces when you look.