Unable to use Validate Assets AQL API

Hi, I was integrating Assets with my app. So i was giving an option like AQL to user where user can enter Assets query language. From Assets page , there is an endpoint
“/gateway/api/jsm/assets/workspace//v1/aql/validate” ,called to validate syntax and this is not open API for Assets. I would like to integrate this API for my app to validate the syntax of Asset Query language. Can any one please suggest how can i integration this api simply , and when i called i was getting some 200 status with response data as “no protocol: /gateway/api/jsm/assets/workspace//v1/aql/validate”

Can any one please help how to resolve this issue with aql/validate API.

I can able to validate the syntax of AQL just by providing the baseURL to this end point and proper workspace id.