You want to retrieve the OData API Metadata but only for one specific entity.
So this KBA explains how you can fetch the metadata of a specific entity instead of fetching the entire instance's metadata.
Now in order to fetch the entire metadata of an instance, we use below API call-
However if we wish to fetch the metadata of some specific entity, we can form the query as follows.
Above query would give us the metadata of only User and Photo entity.
You can refer the KBA #https://launchpad.support.sap.com/#/notes/2215682 for hostname of your instance.
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