Vapi

Building a voice agent that can answer or place phone calls is the job Vapi handles, and it does it through an API built for developers.

Vapi is a voice AI platform for building, testing and deploying agents that talk to people, with uses in call centers, assistants and workflow automation.

It connects to more than 40 apps and supports multiple languages, so one agent setup can cover different markets.

Automated testing lets you check an agent's behavior before it goes live, which matters when the other end of the line is a real customer.

The company cites 99.9% uptime and enterprise-grade reliability.

Expect to need some technical skill to set up and configure Vapi, and the learning curve gets steeper as you use more of its options.

Pricing is enterprise, so you will need to talk to sales for a quote.