$$ \newcommand \MinBalance {b_{\min}} \newcommand \Asset {\mathrm{Asa}} \newcommand \MaxAssetDecimals {\Asset_{d,\max}} \newcommand \MaxAssetNameBytes {\Asset_{n,\max}} \newcommand \MaxAssetUnitNameBytes {\Asset_{u,\max}} \newcommand \MaxAssetURLBytes {\Asset_{r,\max}} $$

Assets

Each account can create assets, named by a globally-unique 64-bit unsigned integer (the asset ID).

Assets are associated with a set of asset parameters, which can be encoded as a msgpack struct:

• The total number of units of the asset created, encoded with msgpack field t. This value MUST be between \( 0 \) and \( 2^{64}-1 \).

• The number of digits after the decimal place to be used when displaying the asset, encoded with msgpack field dc. The divisibility of the asset is given by \( 10^{-\mathrm{dc}} \). A dc value of \( 0 \) represents an asset that is not divisible, while a value of \( 1 \) represents an asset divisible into tenths, \( 2 \) into hundredths, etc. This value MUST be between \( 0 \) and \( \MaxAssetDecimals \) (inclusive) (because \( 2^{64}-1 \) is \( 20 \) decimal digits integer).

• Whether holdings of that asset are frozen by default, a boolean flag encoded with msgpack field df.

• A string representing the unit name of the asset for display to the user, encoded with msgpack field un. This field does not uniquely identify an asset; multiple assets can have the same unit name. The maximum length of this field is \( \MaxAssetUnitNameBytes \) bytes.

• A string representing the name of the asset for display to the user, encoded with msgpack field an. This does not uniquely identify an asset; multiple assets can have the same name. The maximum length of this field is \( \MaxAssetNameBytes \) bytes.

• A string representing a URL that further describes the asset, encoded with msgpack field au. This does not uniquely identify an asset; multiple assets can have the same URL. The maximum length of this field is \( \MaxAssetURLBytes \) bytes.

• A 32-byte hash specifying a commitment to asset-specific metadata, encoded with msgpack field am. This does not uniquely identify an asset; multiple assets can have the same commitment.

• An address of a manager account, encoded with msgpack field m. The manager address is used to update the addresses in the asset parameters using an asset configuration transaction. The manager can destroy the asset if the creator account holds its total supply entirely.

• An address of a reserve account, encoded with msgpack field r. The reserve address is not used in the protocol, and is used purely by client software for user display purposes.

• An address of a freeze account, encoded with msgpack field f. The freeze address is used to issue asset freeze transactions.

• An address of a clawback account, encoded with msgpack field c. The clawback address is used to issue asset transfer transactions from arbitrary source addresses.

Parameters for assets created by an account are stored alongside the account state, denoted by a pair (address, asset ID).

Accounts can create and hold any number of assets.

An account must hold every asset that it created (even if it holds \( 0 \) units of that asset), until that asset is destroyed.

An account’s asset holding is simply a map from asset IDs to an integer value indicating how many units of that asset are held by the account, and a boolean flag indicating if the holding is frozen or unfrozen.

An account that holds any asset cannot be closed.

Asset Minimum Balance Changes

When an account opts in to an asset or creates an asset, the minimum balance requirements for that account increases. The minimum balance requirement is decreased equivalently when an account closes out or deletes an asset.

When opting in to an asset, there is a base minimum balance increase of \( \MinBalance \) μALGO.

When creating an asset, there is a base minimum balance increase of \( \MinBalance \) μALGO.