Apple has announced more verbose API for Siri supported since iOS 12 (https://developer.apple.com/documentation/sirikit/accelerating_app_interactions_with_shortcuts). Users will be able to create their own shortcut phrases for commonly performed tasks. Spotify could run up to its biggest competitor (Apple Music) by introducing Siri support.
Spotify will feed Siri machine what user does and based on that suggest a shortcut, or applications can provide a button that will add a task (like playing a playlist or an album) to Siri with user-defined phrase.
Please consider starting the development as soon as possible so that users won't have to wait long after iOS 12 is released.
Updated on 2018-07-22
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