Build communication features with Twilio: SMS messaging, voice calls, WhatsApp Business API, and user verification (2FA). Covers the full spectrum from simple notifications to complex IVR systems and multi-channel authentication. Critical focus on compliance, rate limits, and error handling. Use when: twilio, send SMS, text message, voice call, phone verification.
Build communication features with Twilio: SMS messaging, voice calls, WhatsApp Business API, and user verification (2FA). Covers the full spectrum from simple notifications to complex IVR systems and multi-channel authentication. Critical focus on compliance, rate limits, and error handling. Use when: twilio, send SMS, text message, voice call, phone verification.
source
vibeship-spawner-skills (Apache 2.0)
Twilio Communications
Patterns
SMS Sending Pattern
Basic pattern for sending SMS messages with Twilio.
Handles the fundamentals: phone number formatting, message delivery,
and delivery status callbacks.
Key considerations:
Phone numbers must be in E.164 format (+1234567890)
Default rate limit: 80 messages per second (MPS)
Messages over 160 characters are split (and cost more)
Carrier filtering can block messages (especially to US numbers)
When to use: ['Sending notifications to users', 'Transactional messages (order confirmations, shipping)', 'Alerts and reminders']
self,
to: str,
body: str,
status_callback: str = None
dict
"""
Send an SMS message.
Args:
to: Recipient phone number in E.164 format
body: Message text (160 chars = 1 segment)
status_callback: URL for delivery status webhooks
Returns:
Message SID and status
"""
# Validate phone number format
if
not
self
return
"success"
False
"error"
"Phone number must be in E.164 format (+1234567890)"
# Check message length (warn about segmentation)
len
159
160
if
1
print
f"Warning: Message will be sent as {segment_count} segments"
try
self
self
return
"success"
True
"message_sid"
"status"
"segments"
except
as
return
self
def
_handle_error
self, error: Twilio
Twilio Verify Pattern (2FA/OTP)
Use Twilio Verify for phone number verification and 2FA.
Handles code generation, delivery, rate limiting, and fraud prevention.
Google found SMS 2FA blocks "100% of automated bots, 96% of bulk
phishing attacks, and 76% of targeted attacks."
When to use: ['User phone number verification at signup', 'Two-factor authentication (2FA)', 'Password reset verification', 'High-value transaction confirmation']
from twilio.rest import Client
from twilio.base.exceptions import TwilioRestException
import os
from enum import Enum
from typing importOptionalclassVerifyChannel(Enum):
SMS = "sms"
CALL = "call"
EMAIL = "email"
WHATSAPP = "whatsapp"classTwilioVerify:
"""
Phone verification with Twilio Verify.
Never store OTP codes - Twilio handles it.
"""def__init__(self, verify_service_sid: str = None):
self.client = Client(
os.environ["TWILIO_ACCOUNT_SID"],
os.environ["TWILIO_AUTH_TOKEN"]
)
# Create a Verify Service in Twilio Console firstself.service_sid = verify_service_sid or os.environ["TWILIO_VERIFY_SID"]
defsend_verification(
self,
to: str,
channel: VerifyChannel = VerifyChannel.SMS,
locale: str = "en") -> dict:
"""
Send verification code to phone/email.
Args:
to: Phone number (E.164) or email
channel: SMS, call, email, or whatsapp
locale: Language code for message
Returns:
Verification status
"""try:
verification = self.client.verify \
.v2 \
.services(self.service_sid) \
.verifications \
.create(
to=to,
channel=channel.value,
locale=locale
)
return {
"success": True,
"status": verification.status, # "pending""channel": channel.value,
"valid": verification.valid
}
except TwilioRestException as e:
returnself._handle_verify_error(e)
defcheck_verification(self, to: str, code: str) -> dict:
"""
Check if verification code is correct.
Args:
to: Phone number or email that received code
code: The code entered by user
R
TwiML IVR Pattern
Build Interactive Voice Response (IVR) systems using TwiML.
TwiML (Twilio Markup Language) is XML that tells Twilio what to do
when receiving calls.
Core TwiML verbs:
: Text-to-speech
: Play audio file
: Collect keypad/speech input
: Connect to another number
: Record caller's voice
: Move to another TwiML endpoint
Key insight: Twilio makes HTTP request to your webhook, you return
TwiML, Twilio executes it. Stateless, so use URL params or sessions.
When to use: ['Phone menu systems (press 1 for sales...)', 'Automated customer support', 'Appointment reminders with confirmation', 'Voicemail systems']
from flask import Flask, request, Response
from twilio.twiml.voice_response import VoiceResponse, Gather
from twilio.request_validator import RequestValidator
import os
app = Flask(__name__)
defvalidate_twilio_request(f):
"""Decorator to validate requests are from Twilio."""defwrapper(*args, **kwargs):
validator = RequestValidator(os.environ["TWILIO_AUTH_TOKEN"])
# Get request details
url = request.url
params = request.form.to_dict()
signature = request.headers.get("X-Twilio-Signature", "")
ifnot validator.validate(url, params, signature):
return"Invalid request", 403return f(*args, **kwargs)
wrapper.__name__ = f.__name__
return wrapper
@app.route("/voice/incoming", methods=["POST"])@validate_twilio_requestdefincoming_call():
"""Handle incoming call with IVR menu."""
response = VoiceResponse()
# Gather digits with timeout
gather = Gather(
num_digits=1,
action="/voice/menu-selection",
method="POST",
timeout=5
)
gather.say(
"Welcome to Acme Corp. ""Press 1 for sales. ""Press 2 for support. ""Press 3 to leave a message."
)
response.append(gather)
# If no input, repeat
response.redirect("/voice/incoming")
return Response(str(response), mimetype="text/xml")
@app.route("/voice/menu-selection", methods=["POST"])@validate_twilio_requestdefmenu_selection():
"""Route based on menu selection."""
response = VoiceResponse()
digit = request.form.get("Digits", "")
if digit == "1":
# Transfer to sales
response.say("Connecting you to sales.")
response.dial(os.environ["SALES_PHONE"])
elif digit == "2":
# Transfer to support
response.say("Connecting you to support.")
response.dial(os.environ["SUPPORT_PHONE"])
elif digit == "3":
# Voicemail
response.say("Please leave a message after
