To implement calendar booking with both voice and SMS in Vapi, create an assistant and attach Google Calendar tools for checking availability and booking. Here’s a quick example using the Server SDK:

typescript
const vapi = new VapiClient({ token: process.env.VAPI_API_KEY! });
await vapi.calls.create({
  transport: { type: "web" }, // or use phoneNumberId for SMS/voice
  assistant: { assistantId: "your-assistant-id" }
});

This setup enables your assistant to handle bookings via both channels. For full steps, see the [appointment scheduling guide](https://docs.vapi.ai/assistants/examples/appointment-scheduling). Source: - [Appointment scheduling assistant](https://docs.vapi.ai/assistants/examples/appointment-scheduling)