Any APIs to send/receive SMS/iMessages from a node (or any such) server to Messages app on iOS?

Does Apple provide any APIs that we can use to send blue imessages or sms on their sms app? Barring Apple Messages for Business? Or are all such APIs private and only choice is to rely on services like Twilio, Telnyx, LoopMessage, SendBlue etc?

Any APIs to send/receive SMS/iMessages from a node (or any such) server to Messages app on iOS?
 
 
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