Harnessing LLMs with TDD

Ive experimented with automated code generating agent systems on localhost multiple times. Ive got some ok results when it was a project spanning over multiple files without any dependencies. But when I tried to cross a milestone of creating a web apps with lets say flask and some db, ive hit a wall. The problem were the dependencies and api hallucinations and the version/api inconsistencies of dependencies in genereated code. The system had a feedback loop with self-written tests, but even the output of the tests fell into neverending loop. Maybe the problem was python? Maybe annotations would help, maybe should use go?