AI Coding Tools Cost One Team $120K/Year — Until They Routed Tasks by Model Tier

A developer running over ten production apps tracked six months of AI coding expenses across Claude Code, Cursor, and Codex, finding combined monthly costs reaching roughly $10,000. The bulk of spending — around 60% — was going to expensive frontier models for routine tasks like formatting, boilerplate, and test generation that did not require that level of capability. After implementing a task-routing system that matched model complexity to task complexity, the team cut monthly spend from $10,000 to around $3,000, a 70% reduction. Mid-tier models handled most implementation work, while frontier models were reserved for architecture and complex debugging, and cheaper models took on docs and formatting. The team also reported a 15% improvement in development speed, attributed to faster response times from smaller models on simpler tasks.