With the right prompt the LLM will solve it in the first place. But this is an issue of not knowing what you don't know, so it makes it difficult to write the right prompt. One way around this is to spawn more agents with specific tasks, or to have an agent that is ONLY focused on finding patterns/code where you're reinventing the wheel.

I often have one agent/prompt where I build things but then I have another agent/prompt where their only job is to find codesmells, bad patterns, outdated libraries, and make issues or fix these problems.