It is a good question
@peace800 and one that I think has sound arguments on each side. As
@wizard has wisely said, based on his long record of successful transactions, most of the time it will not matter. I might even go further and say it can in some cases be a negative, if your description boxes the name into a use that is not what the potential purchaser has in mind.
That being said, I would argue that there are situations where a well worded description can indeed be beneficial. Often the analogy of real estate to domains is used. Imagine you are with two realtors and considering buying a condo or house or commercial property. One provides you with a fancy brochure with nice pictures and text highlighting the positives of the community. Also an information sheet that tells you things like the dimensions of rooms, the assessment, the tax, how much comparable homes have recently sold for, the zoning, etc. The other simply unlocks the door and says here it is. Which are you more likely to buy from?
I think whether descriptions add value depend to some degree on the type of domain name you are selling. If you are selling a well known single dictionary word in .com, a short numbered domain name in .com, or a short acronym in .org or .com, I see little reason. However, if you are selling a domain in a new extension, or an extension that is gaining traction but not yet as well known as the big 3 legacy, something like .ai or .io or .co, I can see that there could be benefits to providing a description that addresses some likely questions and concerns. For brandable names, I am conflicted. I see some danger that the description may distract, since the potential client almost certainly has a somewhat different use in mind.
An additional reason to consider descriptions applies to situations where traffic may help you bring a buyer to a domain that she/he would never have guessed to look for. If you do your own landers as individual web pages, or if you use something like the Epik landers that are in essence single page websites, you can achieve some modest amount of traffic with well chosen descriptions and links. I did a little personal test of this recently looking at about 20 landers I had set up a few months ago on Epik, some with descriptions and some with just the standard content (no domain description). Then I looked back and although a number of the ones with descriptions are in Alexa 5M (none are in Alexa 1M yet) none of the ones without descriptions made the Alexa 5M (a few made 10M). Now this is a small study which does not prove anything definitively, but I am convinced that descriptions can help pages rank to some degree.
There are other points pro and con descriptions which I wrote up
in this blog post just over a year ago. I plan to address the issue in an updated post, either here or on NameTalent, in the not too distant future. I will try to remember to post a link here. Thanks for the good question.
Bob