Hi.
What can be done via the API to confirm yes/no question? Typically, for example...

/system reboot
Reboot, yes? [y/N]:
or
/system routerboard upgrade
Do you really want to upgrade firmware? [y/n]

... Is this possible?

Thanks for answer.

no, that is not possible.

And for your given examples - commands are executed without confirmation as that is done in interactive environments.

If somewhere you see this - please report back so we can fix that.