Can I fetch other documents from the sync function?

I feel a little bit silly asking this question because the docs don’t discuss it at all, so I’m afraid I’m missing something big.

I have a few document types that refer to each other. When syncing one type, in order to determine its channel, I need information out of one of the documents it’s referencing. Is there a way to fetch that referenced document from within the sync function? Or must I make that decision solely based on the document being synced?

It is intentional that no other documents can be accessed from the sync function, since the sync function should be idempotent when re-running it. The state of the sync function must not depend on other documents.

Thank you, @torcolvin, I expected it was a designed-in limitation. This has the unfortunate side effect of causing document bloat and duplication between documents, introducing opportunities for divergence. I’m not quite sure how to best handle that.