Translations:Lightweight Contracts/261/en
From ArdorDocs
The contract runner uses the reference transaction mechanism to link any submitted transaction to the transaction that triggered the contract. This ensures that the confirmation of the new transaction depends on the confirmation of the triggering transaction. This requires a deposit of 10 ARDR for every submitted transaction that is refunded when both transactions are confirmed or the submitted transaction expires. So please make sure the contract runner account has enough ARDR balance to cover this deposit.