OptionalchannelOptionalexternal_Optional. Contact identifier in an external system. If used, channel and identity query parameters can't be used.
OptionalidentityOptional. If set, the channel parameter must be set and external_id can't be used. Used in conjunction with channel to uniquely identify the specified channel identity. This will differ from channel to channel. For example, a phone number for SMS, WhatsApp, and Viber Business.
Optionalpage_Optional. The maximum number of contacts to fetch. The default is 10 and the maximum is 20.
Optionalpage_Optional. Next page token previously returned if any.
Optional. Specifies a channel, and must be set to one of the enum values. If set, the
identityparameter must be set andexternal_idcan't be used. Used in conjunction withidentityto uniquely identify the specified channel identity.