Meta - sendmessage

POST /v1/messages
{
  "recipient_type": "individual",
  "to": "whatsapp-id",
  "type": "audio" | "contact" | "document" | "image" | "location" | "sticker" | "text" | "video",
  
  "audio": {
    "id": "your-media-id",
  }
  
  "document": {
    "id": "your-media-id",
    "caption": "your-document-caption-to-be-sent",
    "filename": "your-document-filename"
  }
  
  "document": {
    "link": "the-provider-name/protocol://the-url",
    "provider": {
        "name" : "provider-name"
    },
    "caption": "your-document-caption"
  }
  
  "document": {
    "link": "http(s)://the-url.pdf",
    "caption": "your-document-caption"
  }
  
  "video": {
    "id": "your-media-id",
    "caption": "your-video-caption"    
  }
  
  "image": {
    "link": "http(s)://the-url",
    "provider": {
        "name" : "provider-name"
    },
    "caption": "your-image-caption"
  }
  
  "image": {
    "id": "your-media-id",
    "caption": "your-image-caption"
  }
  
  "sticker": {
    "id": "your-media-id"
  }
  
  "sticker": {
    "link": "http(s)://the-url",
    "provider": {
      "name" : "provider-name"
    }
  }
}
jeshua cañizares