I was reading a thread that was discussing how to setup a Code Authorization grant type in Postman to make user context API calls. However, the link supplied to a Genesys page on Postman didn't really give information on how to setup Postman for this particular grant type. It was probably updated since that post.
The thread I read:
The problem I'm having now is that when I get the login screen, I login, but the authorization code isn't being sent back to postman. I have the callback/redirect url setup to https://oauth.pstmn.io/v1/callback on the OAuth client.
Also, after I login, I get a Genesys page of "Authorized applications" and shows my OAuth client and its scopes.
It happens that I just wrote a blog on Postman configuration yesterday...
It hasn't been reviewed yet and it is not published on the Dev Center.
But this may help you with Authorization configuration between Postman and Genesys Cloud.
I haven't covered Authorization Code Grant. But if you are trying to get an access token linked to a user (user context), you can use the OAuth PKCE Grant (or OAuth Implicit Grant) that I have described in the blog. Here is the link to the text I have submitted.
If it is ok after review, it will be merged and published as a Blog post on the Developer Center.