A system of multi-modal transmission of packetized data in a voice activated data packet based computer network environment, comprising: a natural language processor component for execution by a data processing system and configured to receive, via an interface of the data processing system, data packets comprising an input audio signal detected by a sensor of a client computing device, the natural language processor component configured to parse the input audio signal to identify a request and a trigger keyword corresponding to the request; a direct action application programming interface of the data processing system configured to generate, based on at least one of the request and the trigger keyword, a first action data structure; a content selector component for execution by the data processing system and configured to receive at least one of the request and the trigger keyword identified by the natural language processor component and to select, based on at least one of the request and the trigger keyword, a content item via a real-time content selection process; an interface management component of the data processing system, configured to: poll a plurality of interfaces to identify a first candidate interface and a second candidate interface within a threshold distance of the client computing device; determine a first resource utilization value for the first candidate interface and a second resource utilization value for the second candidate interface; select, based on a comparison of the first resource utilization value and the second resource utilization value, the first candidate interface as a selected interface to present the content item; provide the content item for delivery in a modality compatible with the selected interface selected based on the comparison of the first resource utilization value and the second resource utilization value; and transmit the content item in the modality to deliver the content item for presentation via the selected interface. a natural language processor component for execution by a data processing system and configured to receive, via an interface of the data processing system, data packets comprising an input audio signal detected by a sensor of a client computing device, the natural language processor component configured to parse the input audio signal to identify a request and a trigger keyword corresponding to the request; a direct action application programming interface of the data processing system configured to generate, based on at least one of the request and the trigger keyword, a first action data structure; a content selector component for execution by the data processing system and configured to receive at least one of the request and the trigger keyword identified by the natural language processor component and to select, based on at least one of the request and the trigger keyword, a content item via a real-time content selection process; an interface management component of the data processing system, configured to: poll a plurality of interfaces to identify a first candidate interface and a second candidate interface within a threshold distance of the client computing device; determine a first resource utilization value for the first candidate interface and a second resource utilization value for the second candidate interface; select, based on a comparison of the first resource utilization value and the second resource utilization value, the first candidate interface as a selected interface to present the content item; provide the content item for delivery in a modality compatible with the selected interface selected based on the comparison of the first resource utilization value and the second resource utilization value; and transmit the content item in the modality to deliver the content item for presentation via the selected interface. poll a plurality of interfaces to identify a first candidate interface and a second candidate interface within a threshold distance of the client computing device; determine a first resource utilization value for the first candidate interface and a second resource utilization value for the second candidate interface; select, based on a comparison of the first resource utilization value and the second resource utilization value, the first candidate interface as a selected interface to present the content item; provide the content item for delivery in a modality compatible with the selected interface selected based on the comparison of the first resource utilization value and the second resource utilization value; and transmit the content item in the modality to deliver the content item for presentation via the selected interface.