A virtual assistant system to control external services via messaging includes a mobile device configured to participate in a messaging session between a plurality of other participants, to receive an input command from a user, to translate the received input command into a semantic atom, and to transmit the semantic atom via a message to the messaging session, and an assistant server configured to receive the semantic atom via the message, the assistant server including at least one plugin, the plugin corresponding to a respective external service and configured to generate a proprietary language command corresponding to the received semantic atom, the proprietary language command controlling the corresponding external service to perform a function corresponding to the input command.