I am really feeling the need for something like this feature.
Airtable does this so well. They have very powerful formulas for working with fields, but also special fields they call "Rollups" and "Lookups" that allow you to work with the data contained in linked records (analogous to linked Nodes in Tana).
Really hope that a feature like this is in the pipeline!
Airtable's API is one of the best implementations I have seen. You get an API that aligns with your own data's schema. https://airtable.com/developers/web/api/introduction
I could imagine a similar approach working really well with Tana. These are the sorts of requests I could imagine finding really useful:
GET /supertags/<supertag_id>/list_nodeswould give you a list of all nodes tagged with that supertagGET /node/<node_id>would give the content for a particular nodeGET /node/<node_id>/descendantswould give you a list of all nodes nested under a particular node. This would be particularly useful when applied to a search node.