i got API's that can be called from an application called AFAS, those API's return metadata specifications of their API's as such and i.e. describe the data elementes returned by the API's. Is such a thing possible to load automatically into DataHub?

You could load these in using the Dataset model in DataHub, but it's not a "perfect fit". Alternatively, you'd have to create a separate "Service" model that can describe metadata around a REST API

@gentle-nest-904: here is what we support for OpenAPI today (https://datahubproject.io/docs/metadata-ingestion/source_docs/openapi) and the PR that added this https://github.com/linkedin/datahub/pull/2706.

(sharing again for visibility) I also pointed @gentle-nest-904 to this feature request in a separate convo via DM 🙂