4. Iterate on a AGENTS.md (or any other similar file you can reuse) that you keep updating every time the agent does something wrong. Don't make an LLM write this file, write it with your own words. Iterate on it whenever the agent did something wrong, then retry the same prompt to verify it actually steers the agent correctly. Eventually you'll build up a relatively concise file with your personal "coding guidelines" that the agent can stick with with relative ease.