feed_url (optional but strongly recommended, string) is the URL of the feed, and serves as the unique identifier for the feed. As with home_page_url, this should be considered required for feeds on the public web.
We should just strongly require feed_url and call it a day, this gives every feed a guaranteed unique identifier to key by.
The JSON Feed spec states:
We should just strongly require
feed_urland call it a day, this gives every feed a guaranteed unique identifier to key by.