[hiq]

> OK, how do I explain that to a junior dev?

They could iterate with their LLM and ask it to be more concise, to give alternative solutions, and use their judgement to choose the one they end up sending to you for review. Assuming of course that the LLM can come up with a solution similar to yours.

Still, in this case, it sounds like you were able to tell within 20s that their solution was too verbose. Declining the PR and mentioning this extra field, and leaving it up to them to implement the two functions (or equivalent) that you implemented yourself would have been fine maybe? Meaning that it was not really such a big waste of time? And in the process, your dev might have learned to use this tool better.

These tools are still new and keep evolving such that we don't have best practices yet in how to use them, but I'm sure we'll get there.

[code_biologist]

They'll improve, but current LLMs (o3, Gemini 2.5 Pro, lesser ones) are also terrible at suggesting non-obvious alternative solutions on their own. You can sometimes squeeze them, adding each obvious but poor approach to a list of "here are things I don't want you to propose" in turn, but often even then they won't get to the answer they should be able to find. The part that is wildly irritating is that once you tell them about the non-obvious simple solution, they act like it's the most natural thing in the world and they knew it the entire time.

Assuming of course that the LLM can come up with a solution similar to yours.

I have idle speculations as to why these things happen, but I think in many cases they can't actually. They also can't tell the junior devs that such a solution might exist if they just dig further. Both of these seem solvable, but it seems like "more, bigger models, probed more deeply" is the solution, and that's an expensive solution that dings the margins of LLM providers. I think LLM providers will keep their margins, providing models with notable gaps and flaws, and let software companies and junior devs sort it out on their own.