Comment by jaktet

Codex /side allows you to toggle to a different pane and maintain an ephemeral or persistent side conversation at the context point which it was launched. It can't natively communicate back to the main thread though. It also allows you to fork the side chat into a new chat. I don't believe it can edit files in side chat mode so the only way to paste context back is fork and do that or just copy and paste. So similar to /btw but with other features.

Claude allows the teams feature and easily spawning co agents or subagents in tmux panes you can interact with (or send to the background). These can communicate with each other. Sometimes you can't interact with one of the tmux agents agents though if it was spawned as some specific type I can't remember.