cannot set API key with `M-x set-variable`: error `Value [...] does not match type choice`

`M-x set-variable chatgpt-shell-[something]-key` is failing for me with the error in title. I've tried both openai and anthropic, obtaining the same error.

EDIT: I'm using chatgpt-shell version 20250722.81, from melpa.

The work around is to set variables with something like `setq`, `M-x customize-set-variable`, or edit `init.el` directly.