In recent years it’s become much easier to talk to machines freely. But rather than talking to machines ourselves, can we have machines talk to others for us? Communication (e.g. phone calls) is an API to the real world. By teaching machines this “protocol of human conversation” we can tap into any service built for humans with instant deployment at zero integration work by any remote party, creating value for both sides. Of course, doing this at scale in consistently high quality and guaranteeing safety and privacy remains challenging. In this talk we bring several tips and advice from having deployed the technology called Google Duplex to several such applications in production, at scale.