Can messages sent through SNS be customized for each protocol used?

Messages sent through Amazon Simple Notification Service (SNS) cannot be customized for each protocol used. When you publish a message to an SNS topic, the message format and content are determined by the default settings of SNS and are sent out in the form appropriate for that particular protocol, such as HTTP, HTTPS, Email, SMS, or Mobile Push.

While you can include various attributes or message structuring to suit particular needs, the SNS service itself does not provide a built-in mechanism to tailor individual message content distinctly for each protocol. This means that while you can format the message for specific protocols when creating subscriptions, once a message is sent to a topic, all subscribers receive it in the format dictated by their protocol without additional customization per subscriber type.

Customizing messages for each protocol would require significant effort on the user's part by potentially using different topics or implementing a message handling layer to format messages accordingly before they reach SNS, which is outside the default functionality offered by SNS.