Sorry you're struggling. There are tons of resources out there from people who've been through the same pain and built up techniques to mitigate them. Matt Pocock's YouTube channel is one good starting place, there are many others. One key tip though is - you own the architecture of your application. If your files have become bloated over several rounds of LLM-generated code, that is primarily your responsibility to observe and push back on that, to ensure your repo as a brief but firm AGENTS.md or CLAUDE.md to describe architectural non-negotiables and some kind of /code-review skill that you give to a second agent to review the first agent's work against those standards. Worried about LLM changes introducing regressions? That's why you have a test suite, and you read what the agent changes to ensure the tests themselves are still checking for correct behaviour.

Your comment comes off as patronising, I don’t know if you intended that or not. These issues are not a matter of ‘holding it wrong’, they’re fundamental to agentic coding.