A rule of thumb I’ve started using is: “if your function name and arguments aren’t good enough to have Copilot tab completion make a cogent attempt at implementing the full behavior, you need more comments/docstrings and/or you need to create utility methods that break down the complexity.”

Alternatively: “if you tab complete a docstring and it doesn’t match what you expect, your code can be clearer and you should add comments and rename variables accordingly.”

This isn’t hard and fast. Sometimes it risks yak shaving. But if an LLM can’t understand your intent, there’s a good chance a colleague or even your future self might similarly struggle.