If you go through the PIP guide there is guidance on what to expect for a medical assessment including the types of questions the assessor may ask. This is not an exhaustive list and you need to bear in mind that it depends on what evidence you submitted in the first place and what particular things the assessor may wish to clarify. So don't be thrown by an unexpected question. (I know of someone who was asked what their last job title was).
They will be observing your husband the entire time and they might ask him to do some physical tests depending on his medical condition.
The assessor will be filling in an online form so they will not always be making eye contact.
