MessageContent
MessageContent is a unique privileged intent that isn't directly associated with any Gateway events. Instead, access to MessageContent permits your app to receive message content data across the APIs.
For example, the content, embeds, attachments, and components fields in message objects all contain message content and therefore require this intent.
Apps without this intent will receive empty values in fields that contain user-inputted content with a few exceptions:
Content in messages that an app sends
Content in DMs with the app
Content in which the app is mentioned
Content of the message a message context menu command is used on