The problem is TUIs. Or at least the assumption you're only supposed to use a TUI. There are plaintext ways to invoke things but the advertised Claude/Codex experience is a TUI. You can't pipe the contents because it's not next - it's instructions to draw to the terminal.
<humor>TUIs are the new podcast! With everyone asking you to invoke tools via a TUI, there was nobody left to write actual tools.</humor>
The problem is TUIs. Or at least the assumption you're only supposed to use a TUI. There are plaintext ways to invoke things but the advertised Claude/Codex experience is a TUI. You can't pipe the contents because it's not next - it's instructions to draw to the terminal.
<humor>TUIs are the new podcast! With everyone asking you to invoke tools via a TUI, there was nobody left to write actual tools.</humor>
TLDR - make sure you support plain text too ;)