> but many of the most common complaints about LLM coding (most notably hallucination) are essentially solved problems if you're using agents.

I have definitely not seen this in my experience (with Aider, Claude and Gemini). While helping me debug an issue, Gemini added a !/bin/sh line to the middle of the file (which appeared to break things), and despite having that code in the context didn't realise it was the issue.

OTOH, when asking for debugging advice in a chat window, I tend to get more useful answers, as opposed to a half-baked implementation that breaks other things. YMMV, as always.