How to fund an account through the API?

Hi, I’m looking at the API docs and can’t find a way to enable users to fund their accounts.

The only info I could find is to do it through the Alpaca’s UI. Also saw you use Plaid, wich we are already using, is it possible to use the credentials we get to fund the user’s account so the user doesn’t have to authenticate their bank twice (we use the user’s bank account for other purposes within our mobile app).

Thanks in advance!