Getting food and water can be a hassle in raid. Not just for raiders, but also for the mage. Mage Vendor allows you to request up to 4 stacks of food and water from a mage that's using the addon. You'll be notified when they accept your request, and they'll trade you when its done.
You can change your request amount at any time before the request is completed, and setting your request amounts to zero will cancel your request.
Mages:
This addon supports multiple mages. Just select the request you wish to take and they'll appear in your "My Requests" tab.
You'll see the amount requested and can complete or cancel a request anytime.