This makes me think - should we be using non-monospace fonts for coding agent chat to improve readability? Wonder if we can get Claude and Codex to do that automatically in supported terminals

Nope. It might improve readability for individual words, but for blocks of code with similar features at irregular lengths, uniform kerning provides structure and a bunch of clean edges that help you visually orient yourself. Just like title text and body text generally need different kerning, so do body text and code.

(As a full time developer for over a decade that got a design degree, I have experimented with it a lot!)