A multi-process application isn't the same as microservices. Microservices is a team organization technique, seeing individual teams operate in isolation, as if they were individual businesses. You can't debug other team's services any more than you can debug what happens when you make a call to OpenAI. That is the level of separation you are up against in a microservices context. If you can, you're on the same team, and thus don't have microservices, just a single service.
What? We have dozens of microservices owned by multiple teams, but nothing stops you from cloning the git repository of another team's microservice and debug it the same way you would debug your own.
Service is provided by people. You, for example, discover a problem with OpenAI's system that you integrate with and the only way you can address it is to employ the services of the people who work for OpenAI. While that is an example of a macroservice (or what we usually just call a service), it playing out in the macro economy, microservice is the same concept except applied in the micro scale.
But you checking out the code and debugging it means that you are providing the service. Where, exactly, do you find the service (micro or otherwise) boundary in this case?
Or are you just struggling to say that your service utilizes multiple applications?