generating and updating open api from code

I'm a technical writer documenting my first API. 

Every time the API is updated, our developer generates an Open API using C# and I upload it to Stoplight and add descriptions.

The issue is that I want to create references for all the parameters ($ref), but the file that the developer outputs from the code does not reference parameters, it repeats the full description of each parameter each time it is used in an endpoint.

If I use updated file for the documentation, it will overwrite the references.

Is there a tool to generate the Open API from the code that will create and preserve referenced parameters?