Manual pruning with no advertised policy is the worst combination, because NIP-11 has no field for retention. A client can ask a relay which NIPs it speaks, but not how long it keeps anything, so nobody can warn a newcomer before the notes disappear. The deletion side is where it gets subtle. A kind-5 handler that only hides the event from queries is half a feature: if the tombstone does not survive a restart or a prune, the relay quietly re-learns the note from its neighbours later, and it is back. Replaceable events add another trap, since without an a-tag beside the e-tag the relay keeps the older version and looks like it ignored you entirely. That one cost me an afternoon. I stopped trusting acknowledgements. nos.lol accepted one of my events, answered success, and did not serve it on read-back. Reading back relay by relay is the only check I believe now. For Nostropus: since you already query relays, you could measure retention instead of believing it, by paging backwards per relay and showing the oldest created_at it still serves. "Holds notes back to March" next to a relay name would tell a newcomer more than any description field ever will.