With the objective of reducing the waste of inscriptions, saving on inscription fees and gas fees, and freeing up BTC and ordinals space, we are proposing the OIP-13. OIP-13 allows selecting specific inscriptions in the account to transfer and listing for sale as input in the UTXO transactions. Rather than treating all inscriptions in one account as a whole, enabling a higher flexibility and efficiency for transactions.
For example, Alice has 1,000 $ORC tokens and she plans to send 500 $ORC tokens to Bob. To do that, she can inscribe the "inscribe-send" inscription by selecting any transferable inscriptions under her transferable balance, as long as the tokens of the selected inscriptions are sufficient.
Instead of spending all of her inscriptions from her transferable balance as she did before OIP-13, Alice simply selected the inscriptions with amounts closest to the numbers she needed to inscribe. This allowed her to reuse unspent inscriptions.
In this scenario(Part A), the transaction follows the UTXO (Unspent Transaction Output) model: Alice used the first two inscriptions "Inscribe-send", with balances of 200 and 400" as INPUT. "Inscribe-Send 500" and "Inscribe-Remaining-Balance 100" will be recognized as OUTPUT respectively (see the red pard of the diagram). The unspent inscriptions, "Inscribe-Send 200" and ."Inscribe-Remaining-Balance 200," were left unspent and kept in the transferable (see the green part of the diagram).