@sbelka.eth You still need a phone number for calls to be done using API/UI. You can use any API like SendGrid for SMS and integrate with VAPI using custom tools.

Thank you for your response! One workaround I found is importing the phone number from OpenPhone to Vonage, allowing us to use the same number on Vapi for the automated portion of our calls. For manual calls and texts, my coworker can use the Vonage Business Communications app to communicate with our clients. Would that make sense?

Is there anything specific about this setup that you'd like me to clarify further? I'm happy to help you through any part of the integration process or explain how to set up particular automations with your Vonage number in Vapi.