I want to develop my own logic for intents and the stuff so I want alexa sends me all the phrase without slots etc... This is because I will send it to my server using an API.
Is it possible?
Yes it is possible. But results are probably worse because you would use Alexa only as an speech to text engine without finding the right intents and filling the slots.
You can create a slot to catch all.
See an old answer by me here: https://stackoverflow.com/a/48686043/3276902
Or from another user here: Alexa - catchall
Than in you backend handle the intent by calling / using your backend logic to process the text.
Just out of curiositiy: You think you could handle the intents better or you just already have a model to process text?