I read the documentation for creating alt text using the REST API.(here)
From what I understand, the endpoint (/1.1/media/metadata/create.json) is a POST request with a JSON body.
Unfortunately, it seems that Apple didn’t implement a method for posting a JSON body, request parameters are always FORM encoded.
The method for creating a request is:
+ (SLRequest *)requestForServiceType:(NSString *)serviceType requestMethod:(SLRequestMethod)requestMethod URL:(NSURL *)url parameters:(NSDictionary *)parameters
SDK Documentation
From what I know, it’s the first api in the REST SDK that needs a JSON body and it breaks the compatibility with the iOS SDK. It would be nice to be able to use the alt text api using the SDK.