It might depend on what you bought and how it was categorised.
For example, if an item is listed as 'used' it should be in working condition.
Something listed as 'for parts/parts only/not working' you would not expect to work.
Honestly though, why on earth would you buy something online that has no pictures and no description?
If you have not paid for the item in question, walk away and don't buy it.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)