Hi Sudhanshu,

we expose an API using Publishing services of mendix like REST Service and Web Service.

We can also use authentication i.e., basic (UserName and Password, Active session) and custom(API Key) as shown in below screenshot.

Go through this link from learning path about Publishing REST API.

REST API

And  we can call it by using the location provided in the API as below screenshot and location endpoints can be changed and root of the url is based on the Environment we are using it.

Refer the below screen Shot :

Note: this is not the Answer

I made 1 small application to check it out. From both swagger console and from POSTMAN i am able to do a GET call. So it should be possible to do any calls.