Automated documentation

I've never seen anybody go back to fixing documentation that goes out of date - but then I've only been software engineering for 30 years. Since nobody ever fixes it, a better strategy is to automate it.

To this end, there is OpenApi (formally Swagger) for documenting REST API endpoints. There are tools that convert the OpenAPI config files into Python, Java, Scala amongst others. You can go the other way and generate code from the OpenAPI config files (example for Python here). 

An example can be found in the Apache Polaris codebase where Gradle builds the classes given a YAML file. IntelliJ quite cleverly recognises it as an OpenApi file and allows you to test the API by invoking the service through the IDE.

IntelliJ's version of Postman

It will even generate the DTOs as defined in the YAML file.