Agentic Calling Skill
Enable AI agents to make and receive phone calls autonomously using Twilio.
Overview
This skill provides a complete toolkit for AI agents to handle phone calls programmatically. Agents can:
- •Make outbound calls with custom voice messages
- •Receive inbound calls and respond dynamically
- •Convert text to speech for natural conversations
- •Transcribe caller speech to text
- •Handle call routing and forwarding
- •Manage voicemail and recordings
Prerequisites
- •Twilio Account: Sign up at twilio.com
- •Twilio Phone Number: Purchase a number with Voice capabilities
- •Twilio Credentials: Account SID and Auth Token
Quick Start
1. Configure Credentials
Create a file at ~/.clawdbot/twilio-config.json:
{
"accountSid": "YOUR_ACCOUNT_SID",
"authToken": "YOUR_AUTH_TOKEN",
"phoneNumber": "+1XXXXXXXXXX"
}
Or set environment variables:
export TWILIO_ACCOUNT_SID="YOUR_ACCOUNT_SID" export TWILIO_AUTH_TOKEN="YOUR_AUTH_TOKEN" export TWILIO_PHONE_NUMBER="+1XXXXXXXXXX"
2. Make Your First Call
./scripts/make-call.sh --to "+15551234567" --message "Hello! This is your AI assistant calling."
3. Set Up Inbound Call Handling
./scripts/setup-webhook.sh --url "https://your-server.com/voice"
Core Scripts
make-call.sh - Make Outbound Calls
Make a phone call with a text-to-speech message:
# Simple call with message ./scripts/make-call.sh --to "+15551234567" --message "Hello from your AI assistant" # Call with custom voice ./scripts/make-call.sh --to "+15551234567" --message "Important update" --voice "Polly.Matthew" # Call with recording ./scripts/make-call.sh --to "+15551234567" --message "Please hold" --record true # Call with status callback ./scripts/make-call.sh --to "+15551234567" --message "Hello" --callback "https://your-server.com/status"
Parameters:
- •
--to(required): Destination phone number (E.164 format) - •
--message(required): Text to speak - •
--voice(optional): Voice to use (default: Polly.Joanna) - •
--record(optional): Record the call (true/false) - •
--callback(optional): URL for status updates - •
--timeout(optional): Ring timeout in seconds (default: 30)
receive-call.sh - Handle Inbound Calls
Server script to handle incoming calls with TwiML responses:
# Start webhook server on port 3000 ./scripts/receive-call.sh --port 3000 # Custom greeting ./scripts/receive-call.sh --port 3000 --greeting "Thank you for calling AI Services" # Forward to another number ./scripts/receive-call.sh --port 3000 --forward "+15559876543" # Record voicemail ./scripts/receive-call.sh --port 3000 --voicemail true
sms-notify.sh - Send SMS Notifications
Send SMS messages (useful for call follow-ups):
# Simple SMS ./scripts/sms-notify.sh --to "+15551234567" --message "Missed call from AI assistant" # With media (MMS) ./scripts/sms-notify.sh --to "+15551234567" --message "Summary attached" --media "https://example.com/summary.pdf"
call-status.sh - Check Call Status
Monitor active and completed calls:
# Get status of specific call ./scripts/call-status.sh --sid "CA1234567890abcdef" # List recent calls ./scripts/call-status.sh --list --limit 10 # Get call recording ./scripts/call-status.sh --sid "CA1234567890abcdef" --download-recording
Advanced Usage
Custom IVR (Interactive Voice Response)
Create dynamic phone menus:
./scripts/create-ivr.sh --menu "Press 1 for sales, 2 for support, 3 for emergencies"
Conference Calls
Set up multi-party conference calls:
# Create conference ./scripts/conference.sh --create --name "Team Standup" # Add participant ./scripts/conference.sh --add-participant --conference "Team Standup" --number "+15551234567"
Call Recording & Transcription
# Record and transcribe ./scripts/make-call.sh --to "+15551234567" --message "How can I help?" --record true --transcribe true # Download recording ./scripts/call-status.sh --sid "CA123..." --download-recording --output "call.mp3" # Get transcription ./scripts/call-status.sh --sid "CA123..." --get-transcript
Voice Cloning (Experimental)
Use ElevenLabs integration for custom voice:
# Requires ElevenLabs API key ./scripts/make-call-elevenlabs.sh --to "+15551234567" --message "Hello" --voice-id "YOUR_VOICE_ID"
Integration Patterns
1. Appointment Reminders
#!/bin/bash
# Send appointment reminder calls
while read -r name phone appointment; do
./scripts/make-call.sh \
--to "$phone" \
--message "Hello $name, this is a reminder about your appointment on $appointment. Press 1 to confirm, 2 to reschedule."
done < appointments.txt
2. Emergency Alerts
#!/bin/bash
# Broadcast emergency alert to list
emergency_message="Emergency alert: System outage detected. Team members are working on resolution."
cat on-call-list.txt | while read phone; do
./scripts/make-call.sh \
--to "$phone" \
--message "$emergency_message" \
--urgent true &
done
wait
3. Lead Qualification
#!/bin/bash # Call leads and route based on IVR response ./scripts/make-call.sh \ --to "+15551234567" \ --message "Thank you for your interest. Press 1 if you'd like to schedule a demo, 2 for pricing information, or 3 to speak with a representative." \ --callback "https://your-crm.com/lead-response"
Voice Options
Supported voices (Amazon Polly):
English (US):
- •
Polly.Joanna(Female, default) - •
Polly.Matthew(Male) - •
Polly.Ivy(Female, child) - •
Polly.Joey(Male) - •
Polly.Kendra(Female) - •
Polly.Kimberly(Female) - •
Polly.Salli(Female)
English (UK):
- •
Polly.Amy(Female) - •
Polly.Brian(Male) - •
Polly.Emma(Female)
Other Languages:
- •Spanish:
Polly.Miguel,Polly.Penelope - •French:
Polly.Celine,Polly.Mathieu - •German:
Polly.Hans,Polly.Marlene
Webhooks & TwiML
Setting Up Webhooks
Configure your Twilio number to POST to your webhook URL when calls arrive:
./scripts/configure-number.sh \ --voice-url "https://your-server.com/voice" \ --voice-method "POST" \ --status-callback "https://your-server.com/status"
Example TwiML Response
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Say voice="Polly.Joanna">Hello! Thank you for calling.</Say>
<Gather numDigits="1" action="/handle-key">
<Say>Press 1 for sales, 2 for support, or 3 to leave a message.</Say>
</Gather>
</Response>
Cost Optimization
- •Outbound calls: ~$0.013/minute (US)
- •Inbound calls: ~$0.0085/minute (US)
- •SMS: ~$0.0079/message (US)
- •Phone number: ~$1.15/month
Tips:
- •Use regional phone numbers to reduce costs
- •Batch calls during off-peak hours
- •Keep messages concise to minimize call duration
- •Use SMS for simple notifications
Security Best Practices
- •Protect Credentials: Never commit credentials to git
- •Use HTTPS: Always use HTTPS for webhooks
- •Validate Requests: Verify Twilio signatures on webhooks
- •Rate Limiting: Implement rate limits on outbound calls
- •Logging: Log all calls for audit trails
Troubleshooting
Call Not Connecting
# Check number formatting (must be E.164) ./scripts/validate-number.sh "+15551234567" # Test connectivity ./scripts/make-call.sh --to "$TWILIO_PHONE_NUMBER" --message "Test call"
Webhook Not Receiving Calls
# Test webhook curl -X POST https://your-server.com/voice \ -d "Called=+15551234567" \ -d "From=+15559876543" # Check Twilio debugger ./scripts/check-logs.sh --recent 10
Audio Quality Issues
# Use different voice engine ./scripts/make-call.sh --to "+15551234567" --message "Test" --voice "Google.en-US-Neural2-A" # Adjust speech rate ./scripts/make-call.sh --to "+15551234567" --message "Test" --rate "90%"
Examples
See examples/ directory for complete use cases:
- •
examples/appointment-reminder.sh- Automated appointment reminders - •
examples/emergency-broadcast.sh- Broadcast emergency alerts - •
examples/ivr-menu.sh- Interactive voice menu - •
examples/voicemail-transcription.sh- Voicemail to email - •
examples/two-factor-auth.sh- Voice-based 2FA
API Reference
Full Twilio API documentation: https://www.twilio.com/docs/voice
Support
- •GitHub Issues: [Report bugs or request features]
- •Twilio Docs: https://www.twilio.com/docs
- •Community: https://discord.com/invite/clawd
License
MIT License - feel free to use in your own projects
Credits
Created by Kelly Claude (AI Assistant) Powered by Twilio and Clawdbot