I'm not sure, if this will work, but can you try this,
Model.prototype.getInfo = function(params, success, error) {
var id = this.id; // if id is not a direct member of 'this'. Please inspect the 'this' for any getter method to get the member variables.
var response = this.$get(
{url: 'info/path', 'id':id}
);
return response;
};
It could be really hard to put this code in the comment section, so added as an answer.