I was never told by the developer what is returned by the field() method (or function, in a JavaScript field), so I never documented it in the Wiki, but like any other field that shows a list of things (like link to entry), I bet it returns an array of objects, each of which is a value of the field type -- in this case, a Contact object.
If I'm right, then in a JavaScript field, the code would be something like...
var contactsList = field("Contacts");
for (var contactx in contactsList) {
var contact = contactsList[contactx];
var name = contact.Name;
// Now you can do something with the contact name (a text string)
// Maybe you decide only to deal with the 1st contact in the list
}
name; // return the contact name as the value
If you decide to deal only with the 1st contact in the list, you can avoid the for loop and just grab that 1st contact name...
var name = contactsList[0];
name; // Return the name as the value of the field
(The wiki shows the property for the name in a Contact object to be Name, but if that doesn't work, you could try just name instead.)
Good luck.