AdsAPI
#1
The Promoted Video Overview page provides a detailed list of steps for uploading and creating Promoted Videos on Twitter. There is also a tutorial that describes how to upload a video to create a video app download card and create a draft Tweet.
Do note that in order to correctly process and prepare a video upload for Promoted Video use, the media_category parameter must be used when uploading a video through the POST media/upload endpoint.
Example: