I'm using the Nopcommerce API plugin, but I'm not sure how to perform some actions the best way.

I have two different Websites: a Nopcommerce-Project with Api Plugin installed and a Umbraco-Project where I want to build a CMS-controlled web shop. The Data comes from Nopcommerce-Project.

A situation I'm not sure how to solve would be when a customer adds an item to the shopping cart.
I see two possibilities here:
1. I send a request from the browser to the CMS, which in turn sends a request to Nopcommerce Api to add the item to the shopping cart.
2. I send the request to Nopcommerce Api directly from the browser with JavaScript for example. This would be a lot easier, but that would also mean that the client needs access to the Authentication Token.

I've already written a message to nop-templates to hear their opinion, but they haven't responded yet..

What would be the best solution?

Thanks, Jonathan