How to create an AI cold-calling agent with the Voice Agent API

An AI cold-calling agent built using the AssemblyAI Voice Agent API and Twilio can efficiently dial prospects, qualify leads through natural conversation, and schedule meetings, simulating the role of a sales development representative (SDR) at a fraction of the cost. The system is designed to handle high volumes of structured calls, ensuring compliance with TCPA and DNC regulations through a robust compliance gate before any call is made. The Voice Agent API handles speech-to-text (STT), language model management (LLM), text-to-speech (TTS), and tool calls through a singular WebSocket, allowing for seamless integration and reducing configuration complexity. Essential components include a dialer to manage calls and respect time-of-day rules, a compliance gate to avoid legal violations, and a tool dispatcher for actions like booking meetings or updating CRM data. The API's pricing model and high speech accuracy make it cost-effective, especially compared to human SDRs, while ensuring high conversion rates by maintaining conversational quality and structured output reliability.