I am assuming that you’re using the prepare_field hook. In this case the values for the field have been adjusted, you’re hooking in just before the field is displayed. They may also be adjusted before the render_field hook as well, I don’t honestly remember. In this case there isn’t really any documentation on what the fields attributes might hold. I do know that _name is a temporary field that holds the real field name and name is altered to hold what will be put into the name attribute of the field.
For me it’s just easier and faster to output the field’s settings so I can look at it rather than look up any documentation if it exists.
