Not setting mandatory managed metadata does not throw any error

Hi everybody,

I am using the Migration API to create a document on SharePoint. I have a managed metadata field which is mandatory on SharePoint content type.

If I don't set the value on the Manifest.xml file I got no error from SharePoint and I want to have a message if this happens. 

Do you know how to force SharePoint to send you a response or how to identify if a mandatory field is missing?