AI Voice Agent: Calls and Automatic Appointment Scheduling

📞 A phone salesperson that never sleeps

Voice agent designed for phone prospecting and appointment scheduling: it answers or initiates the call, converses naturally following a sales script, handles objections, and closes by booking an appointment on the team's calendar.

🏗️ Custom architecture (no expensive middlemen)

• Twilio ConversationRelay for telephony and voice streaming (STT/TTS managed by Twilio).
• Own worker on a VPS running only the LLM logic: every conversation turn goes through the model with the canonical script and call context.
• Human-sounding voice with ElevenLabs, integrated in both the real call and the simulator.
• Key decision: going direct to Twilio instead of platforms like Vapi/Retell — per-minute cost rules once volume scales.

🧪 In-browser simulator

Before spending a cent on telephony, the script is tested in an in-browser call simulator: ringtone, real voice conversation (microphone + TTS), outcome and transcript at the end. Same script and same LLM as the real call — iterating the pitch takes minutes, not phone bills.

📊 Everything measured

Every turn logs token usage and outcome (appointment booked, rejection, follow-up), ready to compute cost per minute and per appointment.