This is some old and probably deprecated information:
by now needs a directory with all possible blender versions, look like this:
generate resolutions is currently run from a .bat file with a .bat command like this:
:: server to use
set BLENDERKIT_SERVER https://www.blenderkit.com
:: api key
set BLENDERKIT_API_KEY avcdasdfaienlksdfoasih
:: blenders folder, see above
set BLENDERS_PATH=F:\blender_processors
:: asset id, if not submitted, uses default search for resolutions
set BLENDERKIT_RESOLUTIONS_SEARCH_ID=3e34afef-31e6-4729-af9c-c181950640ad
:: check if asset needs resolutions - doesn't reupload for assets that already have resolutions files.
set BLENDERKIT_CHECK_NEEDS_RESOLUTION=0
%~dp0blender_processors\2.93.8\2.93\python\bin\python.exe %~dp0blenderkit_server_tools\generate_resolutions_update.py