at means I need to pass a single zip file to 

path

 argument in 

add_files

 , right?

actually the opposite, you pass a folder (of files) to add_files. Then add_files remembers the files location (and pre calculates the hash of the files content). When you call upload it will actually compress the files that changed into a zip file (or files depending on the chunk size), and upload the files to the destination (as specified in the upload call).
If you pass the s3://bucket/folder as output destination for the upload call, clearml will automatically create a subfolder for the dataset and upload the compressed Zip file there.
Is this what you are looking for ?