The AOI from extractdata is a featureset input.
There isn't really a 1 step you can do to get the coordinates of the polygon.
If you just want the features returned as they were submitted, you could add an output parameter of type featureclass and copy the input into the output.
If you really need the coordinates (which will be at least 3 X/Y pairs, if not more), you'll have to either do a cursor to get X/Y at each vertex, or maybe do something like features to points then do an Add XY and return the table values.