Descriptions for Request Attributes in Postman
For example, specify if an element is required or optional, indicate the accepted data type, or use alternative terminology to provide additional clarification for developers who are working with your requests.
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For Postman Pro users publishing internal or public API documentation, these descriptions are displayed in the automatically generated documentation for that collection.
You can hide and show the value and description column in the data editor by clicking on the ellipsis (…) in the top right corner of the editor, and unchecking the columns that you want to hide.