Here's a distinction that may be useful to you: you aren't allowed a single iota in the "description." You are allowed to write whatever you want in the "SUGGESTED description."
The suggested description should ideally tell the editor what not to miss when reviewing your site. Some examples of good things not to do.
"Leading supplier of expostulated widgets to the aerospace, refuse disposal, military, baby food, and all other known industries." [We don't care whom you market to: anybody can use our directory to find you when they need widgets -- whether for straining baby food or making subway Sarin sandwiches.]
"Sells widgets by Acme, Bacme, Cacme, Dacme, Eacme, Facme, Gagme-with-keyword-spam, and all other ["quality"] brands of brand-name widgets." Well, the first two words might survive...
"We are dedicated to (does't matter what you put here -- it's about to get whacked)" It's a website description, not a pop psychological analysis.
"Cheapest prices, telephone 666-666-6666, call for ... " [this is a website description, not a website, and certainly not an advertisement for anything.
In fact, if you make sure that you do not do anything your Marketing 101 textbook recommended, you'll be in good shape. Just tell us who owns the website, and what's on it. "Contains complete plans for enhanced-radiation nuclear device" or "sells fumarolization accessories and baby food strainers."
A typical submitter, having carefully not done all that, would generally be puzzled to eke out ten words of genuine information.