Adding Channels to a Sender

Channels are the communication pathways your sender uses to deliver messages. Each channel has different capabilities, requirements, and use cases. This guide walks you through adding and configuring each channel.

Overview

A sender can have multiple channels configured, enabling features like smart routing and automatic fallback. Here’s a quick reference:

Channel	Requirements	Setup Time	Smart Routing	Fallback
SMS	Phone number with SMS capability	Instant	Yes	Yes
WhatsApp	WABA connection + phone number	5-10 min	Yes	Yes
Email	Verified domain (DKIM records)	10-30 min	No	No
Telegram	Bot token from BotFather	5 min	No	No
Instagram	Meta App + Business Account	10-15 min	No	No
Messenger	Facebook Page	5 min	No	No
Voice	Phone number with voice capability	Instant	No	No

SMS and WhatsApp participate in smart routing and automatic fallback. Email, Telegram, Instagram, Messenger, and Voice are standalone channels that must be explicitly selected.

Prerequisites

Before adding channels:

API key or dashboard access - You need access to your Zavu Dashboard
A sender profile - Create a sender first if you haven’t already
Channel-specific credentials - See each channel section below

Adding Channels via Dashboard

Navigate to Sender Settings

Go to Senders in your Zavu Dashboard and select the sender you want to configure.

Open the Channels Tab

Click the Channels tab to view all available messaging channels and their current status.

Add a Channel

Click the Add button next to the channel you want to enable. Each channel has a specific setup flow.

Complete Configuration

Follow the channel-specific setup wizard to complete the configuration.

SMS Channel

SMS is the most straightforward channel to configure. It uses your sender’s phone number to send text messages.

Requirements

Phone number with SMS capability (purchased through Zavu or your own)
Phone number must be assigned to the sender

Setup via Dashboard

Navigate to your sender’s Channels tab
The SMS channel is automatically enabled when you assign a phone number with SMS capability to your sender
Verify the status shows Active

Setup via API

When creating or updating a sender with a phone number that has SMS capability, SMS is automatically enabled:

import Zavu from "@zavudev/sdk";

const zavu = new Zavu({ apiKey: process.env.ZAVU_API_KEY });

const sender = await zavu.senders.create({
  name: "Support Line",
  phoneNumber: "+15551234567", // Phone with SMS capability
  setAsDefault: true,
});

console.log("Sender created:", sender.id);

from zavudev import Zavudev

zavu = Zavudev(api_key=os.environ["ZAVUDEV_API_KEY"])

sender = zavu.senders.create(
    name="Support Line",
    phone_number="+15551234567",  # Phone with SMS capability
    set_as_default=True,
)

print(f"Sender created: {sender.id}")

require "zavudev"

client = Zavudev::Client.new(api_key: ENV["ZAVUDEV_API_KEY"])

sender = client.senders.create(
  name: "Support Line",
  phone_number: "+15551234567", # Phone with SMS capability
  set_as_default: true
)

puts "Sender created: #{sender.id}"

sender, _ := client.Senders.Create(context.TODO(), zavudev.SenderCreateParams{
	Name:         zavudev.String("Support Line"),
	PhoneNumber:  zavudev.String("+15551234567"),
	SetAsDefault: zavudev.Bool(true),
})

fmt.Println("Sender created:", sender.ID)

<?php
$sender = $client->senders->create([
    'name' => 'Support Line',
    'phoneNumber' => '+15551234567',
    'setAsDefault' => true,
]);

echo "Sender created: " . $sender->id . "\n";

curl -X POST https://api.zavu.dev/v1/senders \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Support Line",
    "phoneNumber": "+15551234567",
    "setAsDefault": true
  }'

Verifying SMS Status

Check if SMS is properly configured:

const sender = await zavu.senders.get({ senderId: "sender_12345" });
console.log("Phone number:", sender.phoneNumber);
// SMS is active if the phone number has SMS capability

sender = zavu.senders.get(sender_id="sender_12345")
print(f"Phone number: {sender.phone_number}")

sender = client.senders.get(sender_id: "sender_12345")
puts "Phone number: #{sender.phone_number}"

sender, _ := client.Senders.Get(context.TODO(), "sender_12345")
fmt.Println("Phone number:", sender.PhoneNumber)

<?php
$sender = $client->senders->get('sender_12345');
echo "Phone number: " . $sender->phoneNumber . "\n";

curl https://api.zavu.dev/v1/senders/sender_12345 \
  -H "Authorization: Bearer $ZAVU_API_KEY"

WhatsApp Channel

WhatsApp requires connecting a WhatsApp Business Account (WABA) through Meta’s Business Platform.

Requirements

Phone number (Zavu number recommended, or your own)
Meta Business account
WhatsApp Business Account (created during setup)

Connection Options

Zavu Phone Number

Recommended. Use a phone number from your Zavu account. Best for dedicated business lines.

Own Phone Number

Setup via Dashboard

Open WhatsApp Setup

In your sender’s Channels tab, click Add next to WhatsApp.

Choose Connection Method

Select whether to use a Zavu phone number (recommended) or your own phone number.

Complete Meta Business Signup

Follow the Meta embedded signup wizard to create or connect your WhatsApp Business Account.

Verify Phone Number

Enter your phone number and verify it. For Zavu numbers, select Call verification (not SMS).

Zavu phone numbers receive verification codes via voice call. Always select Call verification for Zavu numbers.

Enter Verification Code

Enter the verification code displayed in the dashboard to complete setup.

After WhatsApp Connection

Once connected, your sender response will include WhatsApp details:

{
  "id": "sender_12345",
  "name": "Support",
  "phoneNumber": "+15551234567",
  "whatsapp": {
    "phoneNumberId": "123456789012345",
    "displayPhoneNumber": "+15551234567",
    "paymentStatus": {
      "setupStatus": "COMPLETE",
      "methodStatus": "VALID",
      "canSendTemplates": true
    }
  }
}

After connecting WhatsApp, configure your WhatsApp Business Profile and create message templates for outbound conversations.

Email Channel

Email requires domain verification to ensure deliverability and prevent spam filtering.

Requirements

A domain you control (e.g., yourcompany.com)
Access to DNS settings for the domain
Verification typically takes 10-30 minutes

Setup via Dashboard

Navigate to Email Domains

Go to Email Domains in your dashboard and click Add Domain.

Enter Your Domain

Enter your domain (e.g., yourcompany.com).

Add DNS Records

Add the DKIM records provided to your domain’s DNS:

selector1._domainkey.yourcompany.com  CNAME  selector1.dkim.zavu.dev
selector2._domainkey.yourcompany.com  CNAME  selector2.dkim.zavu.dev
selector3._domainkey.yourcompany.com  CNAME  selector3.dkim.zavu.dev

Wait for Verification

Zavu checks DNS records every 5 minutes. Status will change to Verified once complete.

Assign to Sender

In your sender’s Channels tab, enable email and select your verified domain.

DNS propagation typically takes a few minutes but can take up to 48 hours in some cases.

Email Configuration

Configure your email sender identity:

Setting	Example	Description
From Address	`noreply@yourcompany.com`	The address emails are sent from
Reply-To	`support@yourcompany.com`	Where replies are directed

Receiving Inbound Email

To receive inbound emails, enable email receiving on your sender:

await zavu.senders.update({
  senderId: "sender_12345",
  emailReceivingEnabled: true,
});

client.senders.update(
  sender_id: "sender_12345",
  email_receiving_enabled: true
)

client.Senders.Update(context.TODO(), "sender_12345", zavudev.SenderUpdateParams{
	EmailReceivingEnabled: zavudev.Bool(true),
})

<?php
$client->senders->update('sender_12345', [
    'emailReceivingEnabled' => true,
]);

curl -X PATCH https://api.zavu.dev/v1/senders/sender_12345 \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"emailReceivingEnabled": true}'

Telegram Channel

Telegram requires creating a bot through BotFather and connecting it to your sender.

Requirements

Telegram account
Bot token from @BotFather

Create a Telegram Bot

Open BotFather

Open Telegram and search for @BotFather.

Create New Bot

Send /newbot and follow the prompts to name your bot.

Save Bot Token

BotFather provides a token like:

123456789:ABCdefGHIjklMNOpqrsTUVwxyz

Keep your bot token secret. Anyone with this token can control your bot.

Setup via Dashboard

Go to your sender’s Channels tab
Click Add next to Telegram
Paste your bot token
Click Verify to confirm the bot is valid
Click Save to complete setup

Zavu automatically registers the webhook with Telegram when you save.

Setup via API

// Telegram configuration is done via the dashboard
// The sender will include telegram details after setup:
const sender = await zavu.senders.get({ senderId: "sender_12345" });

// Send a Telegram message (requires user to message bot first)
await zavu.messages.send({
  to: "123456789", // Chat ID from inbound message
  text: "Thanks for reaching out!",
  channel: "telegram",
});

# Telegram configuration is done via the dashboard
sender = zavu.senders.get(sender_id="sender_12345")

# Send a Telegram message (requires user to message bot first)
zavu.messages.send(
    to="123456789",  # Chat ID from inbound message
    text="Thanks for reaching out!",
    channel="telegram"
)

# Telegram configuration is done via the dashboard
sender = client.senders.get(sender_id: "sender_12345")

# Send a Telegram message (requires user to message bot first)
client.messages.send(
  to: "123456789", # Chat ID from inbound message
  text: "Thanks for reaching out!",
  channel: "telegram"
)

// Telegram configuration is done via the dashboard
sender, _ := client.Senders.Get(context.TODO(), "sender_12345")

// Send a Telegram message (requires user to message bot first)
client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:      zavudev.String("123456789"),
	Text:    zavudev.String("Thanks for reaching out!"),
	Channel: zavudev.String("telegram"),
})

<?php
// Telegram configuration is done via the dashboard
$sender = $client->senders->get('sender_12345');

// Send a Telegram message (requires user to message bot first)
$client->messages->send([
    'to' => '123456789',
    'text' => 'Thanks for reaching out!',
    'channel' => 'telegram',
]);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "123456789",
    "text": "Thanks for reaching out!",
    "channel": "telegram"
  }'

Telegram users must initiate contact with your bot first. You cannot message users who haven’t started a conversation.

Instagram Channel

Instagram messaging requires connecting through Meta’s Business Platform with your Instagram Business Account.

Requirements

Instagram Business Account (not personal)
Meta Business account
Meta App with Instagram Messaging permissions

Setup via Dashboard

Open Instagram Setup

In your sender’s Channels tab, click Add next to Instagram.

Connect Meta App

Follow the wizard to connect your Meta App and Instagram Business Account.

Grant Permissions

Authorize the required Instagram messaging permissions.

Select Instagram Account

Choose which Instagram Business Account to connect.

Sending Instagram Messages

await zavu.messages.send({
  to: "17841400000000000", // Instagram-scoped User ID
  text: "Thanks for your message!",
  channel: "instagram",
});

zavu.messages.send(
    to="17841400000000000",  # Instagram-scoped User ID
    text="Thanks for your message!",
    channel="instagram"
)

client.messages.send(
  to: "17841400000000000", # Instagram-scoped User ID
  text: "Thanks for your message!",
  channel: "instagram"
)

client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:      zavudev.String("17841400000000000"),
	Text:    zavudev.String("Thanks for your message!"),
	Channel: zavudev.String("instagram"),
})

<?php
$client->messages->send([
    'to' => '17841400000000000',
    'text' => 'Thanks for your message!',
    'channel' => 'instagram',
]);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "17841400000000000",
    "text": "Thanks for your message!",
    "channel": "instagram"
  }'

Instagram has a 24-hour messaging window similar to WhatsApp. You can only message users who have contacted your Instagram account within the last 24 hours.

Messenger Channel

Messenger lets your sender receive and reply to Facebook Page conversations — including Facebook Marketplace chats — by connecting a Facebook Page.

Requirements

A Facebook Page (admin access)
Meta account login during setup

Setup via Dashboard

Open Messenger Setup

In your sender’s Channels tab, click Add next to Messenger.

Connect with Meta

Select Facebook Page

Choose which Facebook Page to connect. Webhooks are subscribed automatically.

Sending Messenger Messages

await zavu.messages.send({
  to: "24025631120151183", // Messenger user ID (PSID)
  text: "Thanks for your message!",
  channel: "messenger",
});

zavu.messages.send(
    to="24025631120151183",  # Messenger user ID (PSID)
    text="Thanks for your message!",
    channel="messenger"
)

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "24025631120151183",
    "text": "Thanks for your message!",
    "channel": "messenger"
  }'

Messenger has a 24-hour messaging window: you can only reply to users who have messaged your Page within the last 24 hours. Marketplace buyer chats arrive through the same channel automatically — see the Messenger guide.

Voice Channel

Voice enables sending text-to-speech messages and receiving voicemails from callers.

Requirements

Phone number with voice capability (purchased through Zavu)
Phone number must be assigned to the sender

Capabilities

Voice Messages

Send short text-to-speech messages to recipients. Your text is converted to natural-sounding speech.

Voicemail

Receive voicemails that are automatically transcribed and appear in your inbox.

Setup via Dashboard

Navigate to Voice Setup

In your sender’s Channels tab, click Add next to Voice.

Verify Phone Number

Ensure your assigned phone number has voice capability enabled.

Configure Voicemail

Set up your voicemail greeting message that callers will hear.

Sending Voice Messages

Send text-to-speech messages to recipients. The text is converted to natural-sounding speech and delivered as a voice call.

await zavu.messages.send({
  to: "+56912345678",
  channel: "voice",
  text: "Your verification code is 1 2 3 4 5 6",
});

zavu.messages.send(
    to="+56912345678",
    channel="voice",
    text="Your verification code is 1 2 3 4 5 6",
)

client.messages.send(
  to: "+56912345678",
  channel: "voice",
  text: "Your verification code is 1 2 3 4 5 6"
)

client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:      zavudev.String("+56912345678"),
	Channel: zavudev.String("voice"),
	Text:    zavudev.String("Your verification code is 1 2 3 4 5 6"),
})

<?php
$client->messages->send([
    'to' => '+56912345678',
    'channel' => 'voice',
    'text' => 'Your verification code is 1 2 3 4 5 6',
]);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+56912345678",
    "channel": "voice",
    "text": "Your verification code is 1 2 3 4 5 6"
  }'

For verification codes, speak digits individually (“1 2 3 4 5 6”) rather than as a number for better clarity.

Receiving Voicemails

When someone calls your Zavu number:

The caller hears your voicemail greeting
They leave a voice message
The message is automatically transcribed
It appears in your inbox with both audio and transcription

Configure webhooks to receive message.inbound events with channel: "voice".

Voicemails are automatically transcribed. You can access both the original audio recording and the text transcription in your inbox and via the API.

Verifying Channel Status

Check via Dashboard

Navigate to your sender’s Channels tab to see the status of each channel:

Status	Meaning
Active	Channel is properly configured and ready
Pending	Setup in progress or awaiting verification
Error	Configuration issue - check details
Not Configured	Channel has not been set up

Check via API

const sender = await zavu.senders.get({ senderId: "sender_12345" });

console.log("Sender ID:", sender.id);
console.log("Phone Number:", sender.phoneNumber);
console.log("WhatsApp:", sender.whatsapp ? "Connected" : "Not configured");
console.log("Email Receiving:", sender.emailReceivingEnabled);

sender = zavu.senders.get(sender_id="sender_12345")

print(f"Sender ID: {sender.id}")
print(f"Phone Number: {sender.phone_number}")
print(f"WhatsApp: {'Connected' if sender.whatsapp else 'Not configured'}")
print(f"Email Receiving: {sender.email_receiving_enabled}")

sender = client.senders.get(sender_id: "sender_12345")

puts "Sender ID: #{sender.id}"
puts "Phone Number: #{sender.phone_number}"
puts "WhatsApp: #{sender.whatsapp ? 'Connected' : 'Not configured'}"
puts "Email Receiving: #{sender.email_receiving_enabled}"

sender, _ := client.Senders.Get(context.TODO(), "sender_12345")

fmt.Println("Sender ID:", sender.ID)
fmt.Println("Phone Number:", sender.PhoneNumber)
if sender.WhatsApp != nil {
	fmt.Println("WhatsApp: Connected")
} else {
	fmt.Println("WhatsApp: Not configured")
}
fmt.Println("Email Receiving:", sender.EmailReceivingEnabled)

<?php
$sender = $client->senders->get('sender_12345');

echo "Sender ID: " . $sender->id . "\n";
echo "Phone Number: " . $sender->phoneNumber . "\n";
echo "WhatsApp: " . ($sender->whatsapp ? 'Connected' : 'Not configured') . "\n";
echo "Email Receiving: " . ($sender->emailReceivingEnabled ? 'true' : 'false') . "\n";

curl https://api.zavu.dev/v1/senders/sender_12345 \
  -H "Authorization: Bearer $ZAVU_API_KEY"

Best Practices

Enable Multiple Channels

Configure both SMS and WhatsApp to enable automatic fallback when one channel fails.

Use Smart Routing

Let Zavu select the optimal channel to reduce costs by up to 80%.

Set Up Webhooks

Configure webhooks to receive inbound messages and delivery status updates.

Verify Before Sending

Test each channel with a single message before sending at scale.

Troubleshooting

SMS Issues

Issue	Solution
SMS not sending	Verify phone number has SMS capability
Messages failing	Check 10DLC registration for US numbers

WhatsApp Issues

Issue	Solution
Verification code not appearing	Select Call verification for Zavu numbers
Meta signup fails	Ensure Facebook Business account has proper permissions
Can’t send messages	Check if 24-hour window is open or use templates

Email Issues

Issue	Solution
Domain not verifying	Check DNS records are correctly configured
Emails going to spam	Verify DKIM records are propagated
Bounces	Verify recipient email addresses are valid

Telegram Issues

Issue	Solution
Bot token invalid	Regenerate token via BotFather using `/token`
Messages not arriving	Verify webhook is registered (automatic on save)
Can’t message user	Users must initiate contact first

Instagram Issues

Issue	Solution
Connection failed	Verify Instagram account is a Business Account
Messages failing	Check 24-hour messaging window
Permission errors	Re-authorize Meta App permissions

Voice Issues

Issue	Solution
Voice not available	Verify phone number has voice capability
Message not delivered	Check recipient answered the call
No transcription	Voicemail may have been too short or unclear

Next Steps

Send Messages

Start sending messages through your configured channels

Configure Webhooks

Set up webhooks to receive inbound messages

WhatsApp Templates

Create templates for WhatsApp outbound messaging

Smart Routing

Learn how Zavu optimizes channel selection

​Overview

​Prerequisites

​Adding Channels via Dashboard

​SMS Channel

​Requirements

​Setup via Dashboard

​Setup via API

​Verifying SMS Status

​WhatsApp Channel

​Requirements

​Connection Options

Zavu Phone Number

Own Phone Number

​Setup via Dashboard

​After WhatsApp Connection

​Email Channel

​Requirements

​Setup via Dashboard

​Email Configuration

​Receiving Inbound Email

​Telegram Channel

​Requirements

​Create a Telegram Bot

​Setup via Dashboard

​Setup via API

​Instagram Channel

​Requirements

​Setup via Dashboard

​Sending Instagram Messages

​Messenger Channel

​Requirements

​Setup via Dashboard

​Sending Messenger Messages

​Voice Channel

​Requirements

​Capabilities

Voice Messages

Voicemail

​Setup via Dashboard

​Sending Voice Messages

​Receiving Voicemails

​Verifying Channel Status

​Check via Dashboard

​Check via API

​Best Practices

Enable Multiple Channels

Use Smart Routing

Set Up Webhooks

Verify Before Sending

​Troubleshooting

​SMS Issues

​WhatsApp Issues

​Email Issues

​Telegram Issues

​Instagram Issues

​Voice Issues

​Next Steps

Send Messages

Configure Webhooks

WhatsApp Templates

Smart Routing

Overview

Prerequisites

Adding Channels via Dashboard

SMS Channel

Requirements

Setup via Dashboard

Setup via API

Verifying SMS Status

WhatsApp Channel

Requirements

Connection Options

Setup via Dashboard

After WhatsApp Connection

Email Channel

Requirements

Setup via Dashboard

Email Configuration

Receiving Inbound Email

Telegram Channel

Requirements

Create a Telegram Bot

Setup via Dashboard

Setup via API

Instagram Channel

Requirements

Setup via Dashboard

Sending Instagram Messages

Messenger Channel

Requirements

Setup via Dashboard

Sending Messenger Messages

Voice Channel

Requirements

Capabilities

Setup via Dashboard

Sending Voice Messages

Receiving Voicemails

Verifying Channel Status

Check via Dashboard

Check via API

Best Practices

Troubleshooting

SMS Issues

WhatsApp Issues

Email Issues

Telegram Issues

Instagram Issues

Voice Issues

Next Steps