Do you mean you want the pushing of the button to prompt the player for input, which is then passed to an API command? You can prompt a player with the query macro construct: ?{Prompt text here|default value} and you can pass that to an API command like this: !api-command ?{Prompt 1|0} ?{Prompt 2|text} and then I'm pretty sure you can just put that as the target of your button in the character sheet, but you might want to ask about that in the character sheets forum.