MGID's "description" field (3)
"Use this section to give more details about your product or service. You can specify discounts, deals or special features. You can emphasize the unique strengths. qualities and selling points and give your potential customers one more reason to click and buy. Finish with a strong call-to-action: what is it that you want your audience to do?"
Does the visitor see the description when looking at the ad? They seem to want you to write a long ass description, so I would think not.
I tried keeping it short but was rejected. What do you guys usually put for the description?
on some placements users will see the description. you can see an example here 
Thanks for the example, that clarifies things.
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