twilio-messaging-overview

What this skill does

## Overview

Twilio's Messaging platform sends and receives messages across multiple channels through a single API. All channels use `client.messages.create()` — only the address format changes.

| Channel | Address format | Rich media | Template required? | Reach | Skill |
|---------|---------------|------------|-------------------|-------|-------|
| **SMS/MMS** | `+15551234567` (E.164) | MMS: images/video, US/CA/AU only | No | Global (180+ countries) | `twilio-sms-send-message` |
| **WhatsApp** | `whatsapp:+15551234567` | Yes (images, docs, video, location) | Outside 24hr window: yes | 190+ countries | `twilio-whatsapp-send-message` |
| **RCS** | Same number (via Messaging Service) | Yes (rich cards, carousels, video) | No | US + expanding globally | `twilio-rcs-messaging` |
| **Facebook Messenger** | `messenger:{page-scoped-id}` | Yes | No | Global | — |

---

## Which Channel Should I Use?

| If you need to... | Use | Why |
|-------------------|-----|-----|
| Reach any phone number | SMS | Universal — works on every phone, no app needed |
| Send rich media globally | WhatsApp | Images, docs, video work worldwide (MMS is US/CA/AU only) |
| Send time-sensitive alerts (OTP, outages) | SMS | Highest open rates, no app dependency |
| Reach opted-in audience at lower cost | WhatsApp | No per-message fee in many markets |
| Run marketing campaigns across channels | Start with `twilio-marketing-promotions-advisor` | Planner skill handles channel mix, compliance, and fallback |
| Send transactional notifications | Start with `twilio-notifications-alerts-advisor` | Planner skill handles urgency-based channel routing |

**Not sure?** Use a Planner skill first — it will qualify your use case and recommend the right channel combination.

---

## Unified API

All channels share `messages.create()`. The only difference is the address format in `from` and `to`.

**Python**
```python
import os
from twilio.rest import Client

client = Client(os.environ["TWILIO_ACCOUNT_SID"], os.environ["TWILIO_AUTH_TOKEN"])

# SMS
sms = client.messages.create(
    from_="+15017122661",
    to="+15558675310",
    body="Your order shipped."
)

# WhatsApp — same API, prefixed addresses
whatsapp = client.messages.create(
    from_="whatsapp:+15017122661",
    to="whatsapp:+15558675310",
    body="Your order shipped."
)
```

**Node.js**
```javascript
const client = require("twilio")(process.env.TWILIO_ACCOUNT_SID, process.env.TWILIO_AUTH_TOKEN);

// SMS
const sms = await client.messages.create({
    from: "+15017122661",
    to: "+15558675310",
    body: "Your order shipped.",
});

// WhatsApp — same API, prefixed addresses
const whatsapp = await client.messages.create({
    from: "whatsapp:+15017122661",
    to: "whatsapp:+15558675310",
    body: "Your order shipped.",
});
```

---

## Onboarding Sequence

Set up messaging in this order. Each step builds on the previous.

### Step 1: Foundation
Get a Twilio number, send your first SMS.
- `twilio-account-setup` → `twilio-sms-send-message`

### Step 2: Sender Strategy
Create a Messaging Service and add your numbers to a sender pool. Use `messagingServiceSid` instead of `from` for all production sends — this enables geo-match, sticky sender, and unlocks compliance features.
- `twilio-messaging-services`

### Step 3: Compliance
Register for A2P 10DLC (required for US SMS traffic). Set up opt-out handling.
- `twilio-compliance-onboarding` → `twilio-compliance-traffic`

### Step 4: Protect
Enable SMS pumping protection (prevents artificial traffic inflation) and compliance toolkit (quiet hours, reassigned number detection) on your Messaging Service.
- `twilio-messaging-services` (Compliance Toolkit + SMS Pumping Protection sections)

### Step 5: Add Channels
Add WhatsApp or other channels. Use Content Templates for cross-channel message formatting.
- `twilio-whatsapp-send-message` → `twilio-content-template-builder`

### Step 6: Monitor
Enable intelligent alerts for error pattern detection. Set up status callbacks for delivery tracking.
- `twilio-messaging-services` (Intelligent Alerts section) → `twilio-messaging-webhooks`

---

## CANNOT

- **Cannot send cross-channel in a single API call** — Each `messages.create()` targets one channel. For multi-channel fallback, implement sequencing in your application (e.g., try SMS, on failure send WhatsApp).
- **Cannot use WhatsApp free-form messages outside the 24-hour window** — After 24 hours since the user's last inbound message, you must use a pre-approved template. See `twilio-whatsapp-send-message`.
- **Cannot send MMS outside US, Canada, and Australia** — MMS is only supported on US/CA/AU numbers. For international rich media, use WhatsApp.
- **Cannot use SMS pumping protection or compliance toolkit without a Messaging Service** — These features are configured per Messaging Service. Raw `from` number sends don't get these protections.
- **Cannot mix channels in a single Messaging Service sender pool** — A Messaging Service manages phone numbers for SMS/MMS. WhatsApp senders are configured separately.
- **Cannot guarantee delivery on any channel** — SMS can be carrier-filtered, WhatsApp can queue-timeout (4 hours). Always implement status callbacks to track delivery.

---

## Next Steps

- **Send SMS:** `twilio-sms-send-message`
- **Send RCS:** `twilio-rcs-messaging`
- **Send WhatsApp:** `twilio-whatsapp-send-message`
- **Set up sender pools and production features:** `twilio-messaging-services`
- **Channel selection for marketing:** `twilio-marketing-promotions-advisor`
- **Channel selection for notifications:** `twilio-notifications-alerts-advisor`