Couldn't find it anywhere in documentation, but is it possible to use upload script with wildcards?
If I use
upload /path/to/files/foo*
the scripts suggest all the full paths of foo* files as a description. Something like
/path/to/files/foo 1 /path/to/files/foo 2 /path/to/files/foo 3
which is, of course, is not what I want. It's the same with the -summary key.

In case of
upload /path/to/files/foo* -descfile:description.txt
I get an error "Both a description and a -descfile were provided. Please specify only one of those."

The workaround is to separately put all the foo* files to a separate folder and use -recursive.
upload -recursive /path/with/files -descfile:description.txt
works fine, but you have to go through the hassle of copying files to a seperate folder.