CampaignCustomMessage

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/amazon-pinpoint/refs/heads/main/json-schema/amazon-pinpoint-campaign-custom-message-schema.json",
  "title": "CampaignCustomMessage",
  "description": "Specifies the contents of a message that's sent through a custom channel to recipients of a campaign.",
  "type": "object",
  "properties": {
    "Data": {
      "allOf": [
        {
          "$ref": "#/components/schemas/__string"
        },
        {
          "description": "The raw, JSON-formatted string to use as the payload for the message. The maximum size is 5 KB."
        }
      ]
    }
  }
}