Hi Shah,
The missing field name in the JSON validation messages has been a long standing issue that will require a request for enhancement. One has been opened for this, see https://ideas.ibm.com/ideas/APICONN-I-777 and I wouldn't be surprised if there were others. Since this one is in state "Future Consideration" I'd suggest you vote for it and comment on your need for it as well.
I'm still retired, but couldn't resist answering this one since it has come up so many times.
Best Regards,
Steve
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Steve Linn
Senior Consulting I/T Specialist
IBM Retired
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