The Hidden Cost of Running LLM Applications at Scale

Everyone watches the model bill. You pick a model, check the pricing page, estimate your request volume, do the math. The number looks fine. You ship. Six months later the bill is three times what you expected and nobody can explain exactly where it went. I have been there. And after building multi-tenant LLM systems in production — serving enterprise clients across multiple services, two different LLM providers, an agentic orchestration layer, and a full retrieval pipeline — I can tell you e...