Have you downloaded our online demos and have you examined the way a webservice is built there? You can see it in this demo: http://demos.telerik.com/aspnet-ajax/tooltip/examples/webservice/defaultcs.aspx
Nevertheless, I am attaching here a simple examplethat shows how to do this. Note how the GET verb is not used and that Autotooltipify will not have effect when targets are declared.
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