The Zap Lifecycle

Which key must a zap receipt be signed with for a client to count it?

• The `nostrPubkey` the recipient's payment server advertised
• The sender's key, from the zap request
• The recipient's own profile key

Where does a client find the amount the sender asked to pay?

• In the receipt's `P` tag
• In the relay's response
• In the `amount` tag of the zap request, which sits inside the receipt's `description` tag