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Documentation Index

Fetch the complete documentation index at: https://docs.relayos.com.br/llms.txt

Use this file to discover all available pages before exploring further.

RelayOS is a REST API that lets you send WhatsApp messages through Meta’s official Cloud API. You get automatic retry with exponential backoff, real-time delivery webhooks, and pricing in Brazilian reais — with zero risk of account bans.

Quick Start

Send your first WhatsApp message in under 5 minutes.

Authentication

Get your API key and authenticate every request.

Guides

Step-by-step walkthroughs for common use cases.

API Reference

Full reference for all public endpoints.

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How it works

1

Create a project and get your API key

Sign up and call POST /v1/projects to receive your API key instantly — no credit card required.
2

Connect your Meta credentials

Provide your Meta Phone Number ID and Access Token via PUT /v1/projects/me/meta-credentials.
3

Send your first message

Call POST /v1/messages with a recipient number and an approved template. RelayOS queues and delivers it automatically.
4

Receive delivery updates

Configure a callbackUrl to receive real-time webhook events as messages move from QUEUED to DELIVERED or READ.

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Key features

Official Meta Cloud API

Built on Meta’s official infrastructure — no unofficial clients, no ban risk.

Priced in BRL

No exchange rate exposure. Pay in reais with transparent local pricing.

Automatic retry

Failed deliveries are retried automatically with exponential backoff.

Real-time webhooks

Get instant POST callbacks when message status changes.

Idempotency keys

Pass an Idempotency-Key header to safely retry requests without duplicate messages.

Template variables

Personalize messages with dynamic variables in any approved WhatsApp template.