Aria Assistant Settings

Parameter Value
Assistant ID a5c4726d-6ae3-49e7-a0bb-f9d6f4cf8f2a
Model Gemini 2.5 Flash via Vapi Google partnership
Voice ElevenLabs Sarah, eleven_multilingual_v2
Transcriber Deepgram Nova 2 Phonecall
Max Duration 600 seconds
Silence Timeout 20 seconds

Tools

checkAvailability

Tool ID: 457948d8-a5bf-42a7-912a-dd8aff3c1630

GET request to Cal.com slots available endpoint. Parameters: startTime, endTime, timeZone. Returns real-time available slots grouped by date. Headers include cal-api-version: 2024-08-13.

bookAppointment

Tool ID: 5a6c034b-351e-4694-91c1-36074892f3d8

POST request to n8n webhook. Parameters: callerName, callerEmail, slotTime, callerTimezone, problemSummary. Routes through n8n to handle nested JSON transformation before hitting Cal.com.

System Prompt Architecture — Version 1.6

Six-phase conversation flow:

  1. Greeting — Name, company, role captured passively
  2. Surface Problem — Use case and urgency signals
  3. Qualify — Budget and timeline directly surfaced
  4. Bridge to Booking — Decision maker authority confirmed
  5. Book Appointment — checkAvailability → offer two slots → bookAppointment
  6. Close — Confirm booking, set expectations, warm close

Key prompt engineering decisions: