How I Cut My AI API Bill by 90% With a Multi-Model Routing System

Last month my Claude API bill was $847. This month it's $73. Same output quality. Here's the system I built. The Problem I run multiple AI-powered services — content generation, email classification, SEO optimization, data extraction. Every call was going to Claude Sonnet because "it works." But most of those calls didn't need Sonnet-level intelligence. Classifying an email as spam? That's a Haiku job. Generating embeddings? Ollama handles that for free. Writing a full article? OK, that's Sonnet