Transaction Output TXO

A TXO is a "Transaction Output." MobileCoin is a ledger built on the "Unspent Transaction Output" model (UTXO).

Transaction Output TXO

In order to construct a transaction, the wallet will select "Unspent Transaction Outputs" and perform a cryptographic operation to mark them as "spent" in the ledger. Then, it will mint new TXOs for the recipient.

Attributes

Name	Type	Description
object	string, value is "txo"	String representing the object's type. Objects of the same type share the same value.
value_pmob	string (uint64)	Available pico MOB for this account at the current account_block_height. If the account is syncing, this value may change.
received_block_index	string (uint64)	Block index in which the TXO was received by an account.
spent_block_index	string (uint64)	Block index in which the TXO was spent by an account.
is_spent_recovered	boolean	Flag that indicates if the spent_block_index was recovered from the ledger. This value is null if the TXO is unspent. If true, some information may not be available on the TXO without user input. If true, the confirmation number will be null without user input.
received_account_id	string	The account_id for the account which has received this TXO. This account has spend authority.
minted_account_i	string	The account_id for the account which minted this TXO.
account_status_map	hash map	A normalized hash mapping account_id to account objects. Keys include "type" and "status".
txo_type	string (enum)	With respect to this account, the TXO may be "minted" or "received".
txo_status	string (enum)	With respect to this account, the TXO may be "unspent", "pending", "spent", "secreted" or "orphaned". For received TXOs received as an assigned address, the lifecycle is "unspent" -> "pending" -> "spent". For outbound, minted TXOs, we cannot monitor its received lifecycle status with respect to the minting account, we note its status as "secreted". If a TXO is received at an address unassigned (likely due to a recovered account or using the account on another client), the TXO is considered "orphaned" until its address is calculated -- in this case, there are manual ways to discover the missing assigned address for orphaned TXOs or to recover an entire account.
target_key	string (hex)	A cryptographic key for this TXO.
public_key	string (hex)	The public key for this TXO, can be used as an identifier to find the TXO in the ledger.
e_fog_hint	string (hex)	The encrypted fog hint for this TXO.
subaddress_index	string (uint64)	The assigned subaddress index for this TXO with respect to its received account.
assigned_address	string (uint64)	The address corresponding to the subaddress index which was assigned as an intended sender for this TXO.
key_image (only on pending/spent)	string (hex)	A fingerprint of the TXO derived from your private spend key materials, required to spend a TXO
confirmation	string (hex)	A confirmation that the sender of the TXO can provide to validate that they participated in the construction of this TXO.

Example

Received and Spent TXO

{
  "object": "txo",
  "txo_id": "14ad2f88...",
  "value_pmob": "8500000000000",
  "received_block_index": "14152",
  "spent_block_index": "20982",
  "is_spent_recovered": false,
  "received_account_id": "1916a9b3...",
  "minted_account_id": null,
  "account_status_map": {
    "1916a9b3...": {
      "txo_status": "spent",
      "txo_type": "received"
    }
  },
  "target_key": "6d6f6f6e...",
  "public_key": "6f20776f...",
  "e_fog_hint": "726c6421...",
  "subaddress_index": "20",
  "assigned_subaddress": "7BeDc5jpZ...",
  "key_image": "6d6f6269...",
  "confirmation": "23fd34a..."
}

TXO Spent Between Accounts in the Same Wallet

{
  "object": "txo",
  "txo_id": "84f3023...",
  "value_pmob": "200",
  "received_block_index": null,
  "spent_block_index": null,
  "is_spent_recovered": false,
  "received_account_id": "36fdf8...",
  "minted_account_id": "a4db032...",
  "account_status_map": {
    "36fdf8...": {
      "txo_status": "unspent",
      "txo_type": "received"
    },
    "a4db03...": {
      "txo_status": "secreted",
      "txo_type": "minted"
    }
  },
  "target_key": "0a2076...",
  "public_key": "0a20e6...",
  "e_fog_hint": "0a5472...",
  "subaddress_index": null,
  "assigned_subaddress": null,
  "key_image": null,
  "confirmation": "0a2044..."
}

View Only Transaction Output ViewOnlyTXO

a minimal txo entity useful for view-only-accounts

Attributes

Name	Type	Description
object	string, value is "view_only_txo"	String representing the object's type. Objects of the same type share the same value.
public_key	string (hex)	The public key for this TXO, can be used as an identifier to find the TXO in the ledger.
value_pmob	string (uint64)	Available pico MOB for this account at the current account_block_height. If the account is syncing, this value may change.
view_only_account_id_hex	string	The local ID for view only account that has the private view key capable of decrypting this txo.
spent	string	Whether or not this txo has been manually marked as spent.
txo_id_hex	string	A synthetic ID created from properties of the TXO. This will be the same for a given TXO across systems.

Example