Agentic Calling

Enable AI agents to autonomously make, receive, transcribe, route, and record phone calls using Twilio with customizable voice messages and IVR support.

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

1. Twilio Account: Sign up at twilio.com
2. Twilio Phone Number: Purchase a number with Voice capabilities
3. Twilio Credentials: Account SID and Auth Token

Quick Start

1. Configure Credentials

Create a file at ~/.clawdbot/twilio-config.json:

json

{
  "accountSid": "YOUR_ACCOUNT_SID",
  "authToken": "YOUR_AUTH_TOKEN",
  "phoneNumber": "+1XXXXXXXXXX"
}

Or set environment variables:

bash

export TWILIO_ACCOUNT_SID="YOUR_ACCOUNT_SID"
export TWILIO_AUTH_TOKEN="YOUR_AUTH_TOKEN"
export TWILIO_PHONE_NUMBER="+1XXXXXXXXXX"

2. Make Your First Call

bash

./scripts/make-call.sh --to "[phone]" --message "Hello! This is your AI assistant calling."

3. Set Up Inbound Call Handling

bash

./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:

bash

# Simple call with message
./scripts/make-call.sh --to "[phone]" --message "Hello from your AI assistant"

# Call with custom voice
./scripts/make-call.sh --to "[phone]" --message "Important update" --voice "Polly.Matthew"

# Call with recording
./scripts/make-call.sh --to "[phone]" --message "Please hold" --record true

# Call with status callback
./scripts/make-call.sh --to "[phone]" --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:

bash

# 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 "[phone]"

# Record voicemail
./scripts/receive-call.sh --port 3000 --voicemail true

sms-notify.sh - Send SMS Notifications

Send SMS messages (useful for call follow-ups):

bash

# Simple SMS
./scripts/sms-notify.sh --to "[phone]" --message "Missed call from AI assistant"

# With media (MMS)
./scripts/sms-notify.sh --to "[phone]" --message "Summary attached" --media "https://example.com/summary.pdf"

call-status.sh - Check Call Status

Monitor active and completed calls:

bash

# 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:

bash

./scripts/create-ivr.sh --menu "Press 1 for sales, 2 for support, 3 for emergencies"

Conference Calls

Set up multi-party conference calls:

bash

# Create conference
./scripts/conference.sh --create --name "Team Standup"

# Add participant
./scripts/conference.sh --add-participant --conference "Team Standup" --number "[phone]"

Call Recording & Transcription

bash

# Record and transcribe
./scripts/make-call.sh --to "[phone]" --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:

bash

# Requires ElevenLabs API key
./scripts/make-call-elevenlabs.sh --to "[phone]" --message "Hello" --voice-id "YOUR_VOICE_ID"

Integration Patterns

1. Appointment Reminders

bash

#!/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

bash

#!/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

bash

#!/bin/bash
# Call leads and route based on IVR response
./scripts/make-call.sh \
  --to "[phone]" \
  --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:

bash

./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

<?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

1. Protect Credentials: Never commit credentials to git
2. Use HTTPS: Always use HTTPS for webhooks
3. Validate Requests: Verify Twilio signatures on webhooks
4. Rate Limiting: Implement rate limits on outbound calls
5. Logging: Log all calls for audit trails

Troubleshooting

Call Not Connecting

bash

# Check number formatting (must be E.164)
./scripts/validate-number.sh "[phone]"

# Test connectivity
./scripts/make-call.sh --to "$TWILIO_PHONE_NUMBER" --message "Test call"

Webhook Not Receiving Calls

bash

# Test webhook
curl -X POST https://your-server.com/voice \
  -d "Called=[phone]" \
  -d "From=[phone]"

# Check Twilio debugger
./scripts/check-logs.sh --recent 10

Audio Quality Issues

bash

# Use different voice engine
./scripts/make-call.sh --to "[phone]" --message "Test" --voice "Google.en-US-Neural2-A"

# Adjust speech rate
./scripts/make-call.sh --to "[phone]" --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