I have written this request in Slack community. I want to post it here one more time.
These days I try to import my old notes to Napkin, but I realize my old notes are too long, they are not suitable for Napkin. David kindly remind me I can clip my old notes into Napkin by new web clipper, now I know how to handle my old notes.
About new thoughts, normally I use Drafts app to send notes everywhere, if we have public input API, I can send notes to both Roam and napkin at same time.
So I think input API is an important way to enrich your Napkin contents, and customize your workflow.