I am wondering if anybody has any information or news regarding the API (if it exists yet?) of the new YouTube Cards (replacing the old annotations).
Is there any beta api information out yet?
I'm referring to this:
Thank you for your help
You can track the YouTube Developer Blog and also subscribe to the revision history of YouTube Data API v3, in order to get the latest info on the API, as soon as it is available. Currently (as of the last version of the API - April 27, 2015) there is no way to manage Cards, and I suspect that there would not be, at least not anytime soon.
I think so because currently even annotations are not fully supported by YouTube Data API v3 (they only added support for setting invideo annotations in v3). I suppose there is a specific reason that this feature has been missing for so long- maybe they don't want to unleash it because they foresee some problems that may arise if they do. It has been requested numerous times in the past by the community (See the last posts in this thread, where a YouTube representative has answered, also this question).
I'll investigate further to see if I can find any more info on future revisions of the API and will update my answer. Meanwhile, you can submit a feature request for Card Management API here. Good luck!
来源：https://stackoverflow.com/questions/29819716/youtube-cards-api