There are a lot of TUIs in existence worth looking at if one is interested or curious about them [0], [1], [2]

[0] https://github.com/rothgar/awesome-tuis

[1] https://terminaltrove.com/explore/

[2] https://github.com/ibraheemdev/modern-unix

Even before Claude Code, I always see htop as the prime example of a good TUI.