At the moment the most useful tool is a multi-line preview feature of grep. e.g. I wanted to find the format for datasets entry, so I did:
grep -r -A2 datasets: model_cards

model_cards/asafaya/bert-mini-arabic/README.md:datasets:
model_cards/asafaya/bert-mini-arabic/README.md-- oscar
model_cards/asafaya/bert-mini-arabic/README.md-- wikipedia

this assumes that the cards are all valid, so that you’re not copying an invalid format from an existing card.
but no urls