Zend certified PHP/Magento developer

I have added a new column in quote item table and I want to add data against this custom field when i add any item in cart through cart API

I have added a new column in quote_item table and want to add this field as a parameter in cart API payload but I don’t how this will happen.

This is what I get when i try to hit add to cart api.
Please let me know. I am new in magento development.
Thanks
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