Hi Francis,
By Queue length do you just mean how many interactions are in the Queue? Or more interested in the the interactions position in that queue?
Position in Queue is available as a system variable in In Q flows. Eg for email it is Email.PositionInQueue, calls it is Call.PositionInQueue
Outside of the In Q flow this is much harder to do.
You can certainly use that API in a DataAction to get the total emails waiting in a queue too, you will just need to be specific about your output template.
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Anton Vroon
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