Adds catalog line items and/or custom line items to a checkout.
The addToCheckout() function returns a Promise that resolves to the updated checkout when the specified items have been added.
Note: When adding catalog items, options.lineItems.catalogReference is required.
Checkout ID.
Items to be added to checkout.
There is 1 error with this status code.
This method may also return standard errors. Learn more about standard Wix errors.