http://sovereign.i2p/proof-of-payment.html
When you enter in the Action Input Parameter(s), and click the Perform Action button, the action will be performed with the output placed in the Action Output text area. The Proof-of-Payment input parameters (txid, txkey, payment_address) must be provided in json format, example: {"txid":"TXID_VALUE","txkey":"TXKEY_VALUE","payment_address":"PAYMENT_ADDRESS_VALUE"} The Proof-of-Payment action output will list the amount received as well as the number of transaction confirmations.