NWC-13: Connection budgets
NWC-13 is an optional draft NIP-47 extension whose get_budget method lets an app query the spending budget of its own connection. It is a parameterless read method with a permission separate from get_balance. A configured budget reports used_budget and total_budget in millisatoshis with a renewal period. An unconfigured budget returns an empty result object, which clients must keep distinct from a configured limit of zero. The budget caps spending, and whether the wallet holds enough funds is verified separately. The spec merged into the nostr-wallet-connect/nwc repository on 20 October as documentation; wallet implementations remain unverified. NWC-13 only queries budgets, and creating or changing one requires separate operations.