---
title: Agente de IA para WhatsApp com Fastify e Zavu
description: Construa um agente de WhatsApp performatico com Fastify, validacao de assinatura e integracao direta ao AI Gateway da Zavu.
date: 2025-12-21
author: Victor Villalobos
locale: pt
source: https://www.zavu.dev/pt/blog/whatsapp-ai-agents-fastify
tags: Agentes IA, WhatsApp, Fastify, Node.js
---

# Agente de IA para WhatsApp com Fastify e Zavu

# Agente de IA para WhatsApp com Fastify e Zavu

Fastify oferece alta performance e tipagem nativa. Veja como criar webhooks de WhatsApp e integrar agentes da Zavu em minutos.

## Setup

```bash
npm init -y
pnpm add fastify fastify-plugin @fastify/formbody @zavudev/sdk dotenv
```

`src/env.ts` carrega as variaveis `ZAVUDEV_API_KEY`, `ZAVU_WEBHOOK_SECRET`, `ZAVU_SENDER_ID`.

## Servidor Fastify

```typescript
import Fastify from 'fastify'
import crypto from 'crypto'
import Zavudev from '@zavudev/sdk'
import { config } from './env'

const app = Fastify({ logger: true })
const zavu = new Zavu({ apiKey: config.ZAVUDEV_API_KEY })

function verifySignature(payload: Buffer, signature?: string) {
  if (!signature) return false
  const digest = crypto
    .createHmac('sha256', config.ZAVU_WEBHOOK_SECRET)
    .update(payload)
    .digest('hex')
  return crypto.timingSafeEqual(Buffer.from(digest), Buffer.from(signature))
}

app.addHook('preValidation', (req, reply, done) => {
  req.rawBody = Buffer.from('')
  req.raw.on('data', (chunk) => (req.rawBody = Buffer.concat([req.rawBody, chunk])))
  req.raw.on('end', () => done())
})

app.post('/webhooks/whatsapp', async (request, reply) => {
  if (!verifySignature(request.rawBody, request.headers['x-zavu-signature'])) {
    return reply.code(401).send({ error: 'invalid signature' })
  }

  const event = request.body as any
  if (event.type === 'message.received') {
    await zavu.senders.agent.reply({
      senderId: config.ZAVU_SENDER_ID,
      contactId: event.data.contact.id,
      messageId: event.data.message.id
    })
  }

  return reply.send({ status: 'ok' })
})

app.listen({ port: 3000 })
```

## Criando o agente

```typescript
await zavu.senders.agent.create({
  senderId: config.ZAVU_SENDER_ID,
  name: 'Fastify Support',
  provider: 'zavu',
  model: 'mistral-large',
  systemPrompt: 'Atenda clientes B2B de forma concisa e tecnica.',
  contextWindowMessages: 12,
  includeContactMetadata: true,
  enabled: true
})
```

## Extensoes recomendadas

- **fastify-rate-limit** para proteger o webhook
- **fastify-helmet** para cabecalhos de seguranca
- **pino** (ja incluso) para logs estruturados

## Recursos do AI Gateway

- Conhecimento (PDFs, URLs)
- Ferramentas HTTP/GraphQL
- Fallback multicanal
- Analytics com latencia e CSAT

## Deploy e observabilidade

1. Hospede no Fly.io/Render (Node 20)
2. Configure health checks e log drains
3. Use `bunx convex dev --once` se tiver workflows relacionados conforme doc interna

Se quiser ver pipelines prontos de agente + CRM, [agende uma demo](/schedule?service=demo).