AI coding tools are not reliable out of the box. Anyone who has used them on a real production project knows this. They work great on greenfield code. They fall apart on a codebase with history. I learned this the hard way. The Problem We have a fintech project that has been running for nearly three years. Two React frontends, an admin panel and a client-facing app, sitting on top of a FastAPI backend with a complex relational database. Multiple tables, heavy joins, financi...