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Schedule appointments from phone calls with AI using Twilio and ElevenLabs
This n8n template creates an intelligent phone receptionist that handles incoming calls, answers FAQs, and schedules appointments to Google Calendar. The system uses Twilio for phone handling, ElevenLabs for voice AI and basic conversations, and n8n for complex scheduling logic—keeping responses snappy by only invoking the workflow when calendar operations are needed.
Who's it for
Businesses that need automated phone scheduling: service companies, clinics, consultants, or any business that takes appointments by phone. Perfect for reducing administrative overhead while maintaining a professional caller experience.
Good to know
Redis memory is essential—without it, the AI must reparse entire conversations causing severe lag in voice responses
Claude 3.5 Sonnet is recommended for best scheduling results
Typical response times: ElevenLabs-only responses <1s, n8n tool calls 2-4s
All placeholder values must be customized or scheduling will fail
How it works
Twilio receives incoming calls and forwards to ElevenLabs voice AI
ElevenLabs handles casual conversation and FAQ responses instantly
When calendar operations are needed, ElevenLabs calls your n8n webhook
n8n checks Google Calendar availability using your business rules
Claude AI agent processes the request, collects required information, and schedules appointments
Redis maintains conversation context across the call
Calendar invites are automatically sent to customers
How to set up
Connect Twilio to ElevenLabs: In Twilio Console, set your phone number webhook to your ElevenLabs agent URL
Configure ElevenLabs tools: Add "Client Tools" in ElevenLabs that point to your n8n webhook for checking availability, creating appointments, and updating appointments
Set n8n webhook path: Replace REPLACE ME in the "Webhook: Receive User Request" node with a secure endpoint (e.g., /elevenlabs-voice-scheduler)
Configure Google Calendar: Replace all REPLACE ME instances with your Calendar ID in the three calendar nodes (Check Availability, Create Appointment, Update Event)
Set up Redis: Configure connection details in the "Redis Chat Memory" node
Customize scheduling prompt: In the "Voice AI Agent" node, replace all bracketed placeholders with your business details:
[TIMEZONE], [START_TIME], [END_TIME], [OPERATING_DAYS], [BLOCKED_DAYS]
[MINIMUM_LEAD_TIME], [APPOINTMENT_DURATION], [SERVICE_TYPE]
[REQUIRED_FIELDS], [REQUIRED_NOTES_FIELDS]
Test: Make a test call to verify availability checking, information collection, and appointment creation
Requirements
Twilio account with phone number
ElevenLabs Conversational AI account
Google Calendar with OAuth2 credentials
Redis instance (for session management)
Anthropic API key (for Claude AI)