true
Plivo generates events when the state of a call changes to let the application know about the progress of the call. Plivo will send one of these values under the Event parameter:

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List of Event values

StartApp

The call was answered and is currently in progress. Calls with this status can be explicitly terminated using the Hangup API.

Transfer

The call was transferred using the Transfer API. This event is sent to the target URL of the XML you return from the transfer URL.

Redirect

The call was redirected using the Redirect XML element.

MachineDetection

Plivo generates this event when the machine_detection parameter is used in the Outbound Call API request. The event is sent to the machine_detection URL.

true