Voice API

The TryVox Voice API enables you to make and receive phone calls, stream real-time audio to LLMs, and control calls programmatically.

Capabilities

The Voice API provides the following features:

Outbound and Inbound Calls

• Make outbound calls to any phone number
• Receive inbound calls via phone numbers you own
• Configure webhooks for call lifecycle events

Real-time Audio Streaming

• Stream audio to and from LLMs in real-time
• Build conversational AI voice agents
• Process audio with custom logic

Call Control

• Transfer calls to other numbers
• Record calls with configurable options
• Play audio files during calls
• Convert text to speech
• Send DTMF tones

Advanced Features

• Multi-party conference calling
• Answering machine detection
• Call duration and timeout controls
• Fallback URLs for error handling

Getting Started

All Voice API endpoints are available at:

https://api.tryvox.io/v1/voice/accounts/{auth_id}/...

Authentication is HTTP Basic with your Auth ID and Auth Token. With curl:

curl -u $TRYVOX_AUTH_ID:$TRYVOX_AUTH_TOKEN \
  https://api.tryvox.io/v1/voice/accounts/$TRYVOX_AUTH_ID/calls

See Authentication for the full credential format.

Outbound Call Prerequisite

Before you can place an outbound call, the from number must be a verified caller ID on your account. Inbound calls work without this step — only outbound is gated.

API Reference

Call Lifecycle

1. Initiate - Call is created via API or inbound to your number
2. Ringing - Optional ring_url webhook is called
3. Answered - answer_url webhook is called, returns VoxML instructions
4. Active - Call is in progress, actions can be performed
5. Ended - Optional hangup_url webhook is called with call details