Mkv golf gti snapped? pipe ID please

[bigandclever]

Forgive me for I am mechanically inept.

Started the golf this morning, with very rough idle (idle revs about 600rpm) and a hissing noise from under the bonnet. There is a pipe with what looks like a sheared metal end that was hissing for a while and is now silent. For the photo below I’ve moved it forwards a couple of inches from its original position behind the other pipes to the right of the picture. I can’t see or feel where it would’ve been attached.

My questions are:
what is the pipe?
what has it snapped off?
is the car driveable without likely damage?
is it a garage fix? - that’s a ‘yes’ by the way, but I will need to at least know what I’m asking to be fixed

I hope it will be clear enough for those in the know. Following the pipe backward it seems to disappear into the rear left of the engine bay. It’s a mkv 2005 golf gti.

[anonymous-user]

Vaccum pipe, will smell oiley but is safe to drive until you get it fixed.

[bigandclever]

Thanks! Really helps.