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While all of these options are always available, the options are condensed to those unique actions and presented to the connected client in a number of ways. In other words, when the queue is empty, the only presented option is Now because there is nothing to modify. Sending Replace in such a scenario would perform the same exact action as Now. The list of options is communicated to the connected client via the LocalQueueOptions status event or as a menu when indicating playback via the ClarifyTitleIntent command. To ensure MMS knows the client supports this functionality, be sure to indicate as such by sending SetOption supports_playnow=true during the preamble. See the Setting Additional Options section above for more details.
The intended option is communicated to the server by appending it to the end of the Play<Container> command after the container’s GUID. For example, PlayAlbum c8507e3c-a5c0-4503-bd87-0b711580987e Replace. For items where a listAction is provided and that listAction is ClarifyTitleIntent, append the verb to the end of that command. For example, ClarifyTitleIntent 1609d2f0-b7c8-4996-9a48-4f434ad436e0 Next. Leaving the verb off will result in a menu for the user to select from unless there is only one action available, in which case MMS will perform that action.
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