nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg is there a ecash API implementation or standard that exists yet? 

Like L402 for lightning, but instead of having a macaroon of the payment hash and a preimage of the lightning invoice you just put the ecash directly in the API request