A CDE controlled identifier recording the user's context on the CDE. For example which project and folder the user was on. If the client provides the server_context in subsequent calls then the CDE will attemp to load the UI at the same place.
supported_file_extensionsstring[]
The client may optionally provide an array of accepted file extensions that should be opened during this flow. The CDE server UI should make an attempt to only show files matching these extensions to the user for the download selection or help the user in selecting the desired files. However, the server does not have to guarantee that only files matching the extensions will be selected. The extensions here must contain the dot separator.