I didn't see this on the first couple of pages, but I recently noticed a new feature which allows you to source your scan uploads. What my question is is that is it enough that we just fill that portion out and not write any more about it in the description box?

An example would be
from website (specify)
www.filledin.com

and then the description would be
People dancing

and not stating anything else relating to the scan besides the content of it

That would be perfectly fine since you have acknowledged whether or not you did the scan (if a site is provided, it's obvious you found the scan, hence didn't do it)

Description isn't really necessary. It might help a tiny bit when people search for gallery items, but they don't have to be long if it's a scan (different story for Indy Art and Wallpapers ).

http://support.minitokyo.net/policy/ for more information, if you feel you need to read more :3

Dodgy as it may be, it is perfectly fine, however that leaves a wide opening that if someone submits that exact same scan a day later with a full source and location yours will be wiped as a lower description submission. Bottom line is a better description is encouraged and recommended however the choice is yours.

EDIT: Just realised kuroimisa beat me to it, well you have two mods in agreement, always a good sign.