Easy Way

Send your first message in seconds. Zavu handles channel selection, delivery optimization, and fallbacks automatically.

Quick Start

import Zavudev from '@zavudev/sdk';

const zavu = new Zavudev({
  apiKey: process.env['ZAVUDEV_API_KEY'], // This is the default and can be omitted
});

const result = await zavu.messages.send({
  to: "+14155551234",
  text: "Hello from Zavu!",
});

import os
from zavudev import Zavudev

zavu = Zavudev(
    api_key=os.environ.get("ZAVUDEV_API_KEY"),
)

result = zavu.messages.send(
    to="+14155551234",
    text="Hello from Zavu!"
)

require "zavudev"

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

result = client.messages.send_(
  to: "+14155551234",
  text: "Hello from Zavu!"
)

client := zavudev.NewClient(option.WithAPIKey(os.Getenv("ZAVUDEV_API_KEY")))

result, _ := client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:   zavudev.String("+14155551234"),
	Text: zavudev.String("Hello from Zavu!"),
})

<?php
$client = new Zavudev\Client(apiKey: getenv('ZAVUDEV_API_KEY'));

$result = $client->messages->send([
    'to' => '+14155551234',
    'text' => 'Hello from Zavu!',
]);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVUDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+14155551234",
    "text": "Hello from Zavu!"
  }'

You can optionally specify a sender by passing zavuSender (TypeScript), zavu_sender (Python), or the Zavu-Sender header (cURL). If omitted, your project’s default sender is used.

That’s it. Zavu automatically:

Respects user preference: When a user messages you first, we reply on the same channel they used
Optimizes outbound: For business-initiated messages, selects the optimal channel based on cost and delivery rates
Falls back intelligently: Tries alternative channels if delivery fails
Tracks everything: Delivery status updates via API and webhooks

How It Works

When you send a message without specifying a channel, your default Sender handles routing:

Your Message → Default Sender → Smart Routing → Best Channel → Delivery

Senders

A Sender is a configuration that defines how messages are sent. Each Sender has:

Channels: Which channels are available (SMS, WhatsApp, etc.)
Routing Policy: smart (automatic) or manual (you choose)
Phone Numbers: Configured for each channel

Create your first Sender in the Dashboard or via the API.

Using a Specific Sender

If you have multiple Senders (e.g., “Marketing” and “Support”), specify which one to use:

const result = await zavu.messages.send({
  to: "+14155551234",
  text: "Your order has shipped!",
  zavuSender: "snd_abc123",
});

result = zavu.messages.send(
    to="+14155551234",
    text="Your order has shipped!",
    zavu_sender="snd_abc123"
)

result = client.messages.send_(
  to: "+14155551234",
  text: "Your order has shipped!",
  zavu_sender: "snd_abc123"
)

result, _ := client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:         zavudev.String("+14155551234"),
	Text:       zavudev.String("Your order has shipped!"),
	ZavuSender: zavudev.String("snd_abc123"),
})

<?php
$result = $client->messages->send([
    'to' => '+14155551234',
    'text' => 'Your order has shipped!',
], ['zavu_sender' => 'snd_abc123']);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVUDEV_API_KEY" \
  -H "Zavu-Sender: snd_abc123" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+14155551234",
    "text": "Your order has shipped!"
  }'

Specifying a Channel

For full control, specify the channel directly:

const result = await zavu.messages.send({
  to: "+14155551234",
  text: "Hello!",
  channel: "whatsapp",
});

result = zavu.messages.send(
    to="+14155551234",
    text="Hello!",
    channel="whatsapp"
)

result = client.messages.send_(
  to: "+14155551234",
  text: "Hello!",
  channel: "whatsapp"
)

result, _ := client.Messages.Send(context.TODO(), zavudev.MessageSendParams{
	To:      zavudev.String("+14155551234"),
	Text:    zavudev.String("Hello!"),
	Channel: zavudev.String("whatsapp"),
})

<?php
$result = $client->messages->send([
    'to' => '+14155551234',
    'text' => 'Hello!',
    'channel' => 'whatsapp',
]);

curl -X POST https://api.zavu.dev/v1/messages \
  -H "Authorization: Bearer $ZAVUDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+14155551234",
    "text": "Hello!",
    "channel": "whatsapp"
  }'

Available channels: sms, whatsapp

Response

A successful request returns the message details:

{
  "message": {
    "id": "msg_abc123",
    "to": "+14155551234",
    "text": "Hello from Zavu!",
    "channel": "whatsapp",
    "status": "queued",
    "createdAt": "2024-01-15T10:30:00.000Z"
  }
}

Status	Description
`queued`	Message accepted, pending delivery
`sent`	Sent to carrier/provider
`delivered`	Confirmed delivered
`read`	User opened the message (WhatsApp only)
`failed`	Delivery failed

Next Steps

Smart Routing - Learn how automatic channel selection saves up to 90% on messaging costs
SMS Guide - SMS-specific features and best practices
WhatsApp Guide - Rich messaging with media, buttons, and templates

API Reference

Send a message — full HTTP reference for the /v1/messages endpoint
Get a message by ID — retrieve delivery status and metadata
List messages — fetch sent messages with filtering and pagination

Getting Started

Build agents

Send & receive

Operate

Developer tools

Integrations

Quick Start

How It Works

Senders

Using a Specific Sender

Specifying a Channel

Response

Next Steps

API Reference

​Quick Start

​How It Works

​Senders

​Using a Specific Sender

​Specifying a Channel

​Response

​Next Steps

​API Reference

Quick Start

How It Works

Senders

Using a Specific Sender

Specifying a Channel

Response

Next Steps

API Reference