Built on the Attestations NIP (31871); a listing is the Assertion Event:
- Seller 'Mark as sold' now opens a dialog (buyer npub + self-reported method +
optional amount) that marks the listing sold AND publishes a trade attestation
- Buyer sees 'Confirm this trade' on the listing and publishes the mirror
attestation -> mutual pair = a verified trade
- useTradeReputation aggregates sales/purchases/verified + counterparties
- Profile 'Trades' card; seller 'N verified trades' badge on listing cards
- NIP.md documents kind 31871 usage + our p/method/amount extensions
Payment method is self-reported metadata, never proof of payment.