MPC Coin Management
Introduction
In MPC-driven mode, new EVM, ERC-20 and TRC-20 coins can be added to your Custody Infrastructure system directly from the desktop application. Then the coin must be imported into Impenetrable Vault. For information about importing coins into the Impenetrable Vault, see Coin Management.
This article covers the following EVM, ERC-20 and TRC-20 operations from the desktop in MPC-driven mode:
- Editing the EVM nameEditing the EVM name
Coin Management now supports up to 999 EVMs, ERC-20s and TRC-20s coins on the system, effectively removing the limitations present in previous versions.
Who Adds EVMs
Adding EVMs via the Desktop app is governed by the Add EVMs and tokens policy rule. Only a user covered by this policy can add EVMs via the MPC desktop. See Policy Engine to learn about policy rules.
How to Add an EVM via the Desktop
We preload a number of EVMs into the system. Adding one of these preset coins to your deployment is a straightforward process of assigning the current fiat value and configuring fees, then adding and approving it.
You can also add new custom EVM coins to your system. Adding a custom coin is a more involved process.
Both processes are outlined below.
To add a preset EVM to your Custody Infrastructure system via the MPC:
On the MPC, navigate to Admin Panel > Coin management. Click the 
button.
The Add a new coin dialog opens.
In the Coin type drop down list, select EVM.
In the Network drop down list, select a coin.
The Value in Fiat field automatically fills in.
In the Typical transaction type drop down list, select the most appropriate option for your transaction needs.
The transaction type helps set predefined max gas limits for your transactions to help make your transaction process quicker and more efficient. The gas fees that this setting applies to your transactions can be edited if they do not match your needs at the time.
Enter the Node URL.
Use the open link button to open Chainlist.org in your browser to help find the public node, or enter a private node URL.
The Fee settings for this coin are automatically set and can be edited by openning the More details section.
The Fee settings to edit are:
- Gas limit: How much gas you are willing to pay on a transaction.
- Max fee: The maximum fee to pay on a transaction.
- System max fee: This is the maximum fee you are willing to pay for transactions between two system addresses (e.g. Collector and Auto Balancing actions).
Click Add. The preset EVM is ready for approval.
After being approved in an approval session, the new preset EVM is activated on your system and is visible and useable via both the MPC desktop and mobile apps. To access this coin on the Impenterable Vault, you need to perform an Import from MPC process on the Cold Vault. For information about importing coins into the Impenetrable Vault, see Add an EVM to the system.
Auto-balancing is only available if your system has an Impenetrable Vault.
Custody Infrastructure can support most, but not all, EVMs. If you want to add a custom EVM to your system, first contact support. We will let you know whether we can support the EVM you want to add.
If the EVM is supported, we will provide you with an activation code, which is essential for adding a new custom EVM coin. Have the code ready when you add the custom EVM.
On the MPC, navigate to Admin Panel > Coin management. Click the button.
The Add a new coin dialog opens. Select 
Add custom EVM at the bottom of the dialog window.
Select EVM coin > EVM custom coin. A form opens to configure the details of the new EVM.
Fill out the information about the EVM:
In the Info section:
- Name: The name of the EVM.
- Chain ID: The ID of the chain.
- Symbol: The symbol of the EVM.
- Node URL: Input the node URL.
- EVM type: The EVM type sets the fee structure for this coin. There are 6 options:
- Vanilla Mode - Fees handled in the same way as in the Ethereum mainnet
- Turbo Blocks - Requires a gas limit over 21k for simple transactions
- Hidden Toll - Consumes a fee greater than the given gas fee
- Gaszilla - Requires both a gas limit over 21k for simple transactions and consumes a fee greater than the given gas fee
- Heavy Deploy - During initialization, sending to a new address involves a higher costs
- Free Ride - Gas price may be 0
- EIP type: Choose whether the EVM is Legacy or London fork.
In the Fiat section:
- Value in fiat: Populate this with the coin's value.
In the Fee section:
- Gas limit: How much gas you are willing to pay on a transaction.
- Max fee: The maximum fee to pay on a transaction.
- System max fee: This is the maximum fee you are willing to pay for transactions between two system addresses (e.g. Collector and Auto Balancing actions).
In the Code section:
- Activation Code: The code provided to you by the Customer Success team.
Click Add. The custom EVM is ready for approval.
After being approved in an approval session, the new custom EVM is activated on your system and is visible and useable via both the MPC desktop and mobile apps. To access this coin on the Impenterable Vault, you need to perform an Import from MPC process on the Cold Vault. For information about importing coins into the Impenetrable Vault, see Add an EVM to the system.
Auto-balancing is only available if your system has an Impenetrable Vault.
Who Adds ERC-20s
Adding ERC-20s via the Desktop app is governed by the Add EVMs and tokens policy rule. Only a user covered by this policy can add ERC-20s via the MPC desktop. See Policy Engine to learn about policy rules.
How to Add an ERC-20 via the Desktop
We preload a number of ERC-20s into the system. Adding one of these preset coins to your deployment is a straightforward process of assigning the current fiat value and configuring fees, then adding and approving it.
You can also add new custom ERC-20 to your system. Adding a custom coin is a more involved process.
Both processes are outlined below.
Who adds TRC-20s
Adding TRC-20s via the Desktop app is governed by the Add EVMs and tokens policy rule. Only a user covered by this policy can add TRC-20s via the MPC desktop. See Policy Engine to learn about policy rules.
How to Add an TRC-20 via the Desktop
We preload a number of TRC-20 into the system. Adding one of these preset coins to your deployment is a straightforward process of assigning the current fiat value and configuring fees, then adding and approving it.
You can also add new custom TRC-20 to your system. Adding a custom coin is a more involved process.
Both processes are outlined below.
To add a custom TRC-20 to your Custody Infrastructure system via the MPC:
On the MPC, navigate to Admin Panel > Coin management. Click the button.
The Add a new coin dialog opens. Select 
Add custom TRC20 at the bottom of the dialog window.
In the Coin type drop down list, select TRC20.
In the Token drop down list, select a token.
The Value in Fiat field automatically fills in.
In the More details section, set the Gas Limit.
Click Add. The custom TRC20 is ready for approval.
After being approved in an approval session, the new custom TRC-20 is activated on your system and is visible and useable via both the MPC desktop and mobile apps. To access this coin on the Impenterable Vault, you need to perform an Import from MPC process on the Cold Vault. For information about importing coins into the Impenetrable Vault, see Add a TRC-20 to the system.
Auto-balancing is only available if your system has an Impenetrable Vault.
Updating MPC Coin Price Automatically
Configuring
In MPC-driven mode, you can configure the MPC to track and adjust your active coins' prices automatically. This process only changes the price on the MPC. Cold Vault currency values are not changed by automatic MPC price adjustments.
The system or users cannot drop a coin's value below the "Min Price in Fiat" set for that coin on the Cold Vault. To set a price below that requires the Coin Management interface on the Cold Vault.
Raising a coin's Min Price in Fiat above its current MPC price causes the price on the MPC to be reset to the new minimum.
On the MPC, navigate to Adnmin Panel -> Coin Management tab.
Select the Price Update Settings button in the upper-right of the panel. The Price update setting menu opens.
Set the percent range by using the slider. This defines an amount of change (both value increase and decrease) that you trust the system to handle automatically. This percentage is applied to all coins.
A base value is set when the coin is activated. The percent of change is relative this base price. The system notifies you if it cannot update a coin because the new value falls outside the percentage window you set. In this situation you can either adjust the base price or increase the percentage.
OPTIONAL: Allow specific currencies to ignore the percentage limits. These currencies will automatically have their prices set as high or low as the market dictates. This can send system values to the moon (or through the floor), and can have an outsize impact on how much currency users can transfer vis-a-vis their limits.
- Select the down arrow in the Add currency dropdown. All active currencies are displayed.
- Select any currencies to include in the Unlimited coins list. The coins are added to the list when you click out of the dropdown. Each coin selected appears as a tile on the list.
To remove a coin from the Unlimited coins list, select the X in the upper right corner of the coin's tile on the list.
Select Save to finalize your settings and initiate an administrative change session.
How it Works
The MPC (including the cosigners) checks the price of each active currency once an hour. It uses three providers:
If any provider fails to provide a value for a specific coin, it does not adjust that coin's price and checks again in an hour.
If the system receives a price from all three sites, it takes the highest (coinMaxVal) and lowest (coinMinVal) quoted price and checks whether they fall within 5% of one another:
(coinMaxVal - coinMinVal) <= .05 * coinMinValIf the two values are not within 5% of one another, it does not adjust that coin's price and checks again in an hour.
If all three values are received and pass the 5% check, the system checks the configuration against the coinMaxVal.
Is the coinMaxVal higher than the minimum value set for that coin on the Cold Vault? If yes, continue.
The system checks that the coinMaxVal is above the minimum value for the coin set on the Cold Vault, and then checks that the coinMaxVal falls within the configured percentage window. If the value falls above or below the window, the system adjusts the coin's price to the highest or lowest allowable. Otherwise, the price remains the same.
If the coinMaxVal is higher than the minimum value set for the coin on the Cold Vault the value is not updated.
- Does the coinMaxVal fall within the configured percentage window? If the value falls above or below the window, the system adjusts the coin's price to the highest or lowest allowable.
After the configuration check is passed, the coin's value on the MPC is set to the coinMaxVal.
Coin price error messages
Coin prices should automatically update as described above, however, if the coin prices are not updated, inaccurate transactions can occur if there is a discrepency between the price listed in the uMPC and the real price.
If the price listed in the Impenetrable Vault remains lower than the real value, and exceeds the percent price difference set in the Automatic update price setting, a warning sign appears in the Coin Management for the affected coins.
By hovering over the warning sign, a pop up window appears explaining the reason for the warning and giving a suggested solution.
Deactivating Coins
In most Desktop systems (either Cold-driven or MPC-driven) a coin cannot be deactivated on the Desktop app, only via the Impenetrable Vault.
To deactivate any Native, EVM, ERC-20 or TRC-20 coin, first ensure the coin is imported to the Impenetrable Vault. Then deactivate the coin by deselecting the Active checkbox in the Impenetrable Vault's Coin Management interface.
Removing Coins in a MPC-only Setup
In a MPC-only system, coins can be removed from the system so that the admin user has a way to control coin management. Removing coins that are not used in the system improves performance and the user experience by reducing unwanted coins listed on the screen.
To remove a coin:
Go to Admin panel > Coin Management, the Remove coins button is in the upper-right corner next to Add coins.
Select Remove coins. The Remove coins window opens listing all of the coins that can be removed. Use the filter or search options to locate the coin or coins to be removed.
Select the checkbox next to each coin you want to remove.
Select Remove coins to open the Review screen.
The Review screen lists any contacts or policies associated with each coin. This allows you to review the effects of removing the coin from the system.
To keep a coin, uncheck the box.
After review, select Remove coins to complete the process.
Editing the EVM name
The user can update and edit the name of a pre-set or user -defined EVM coin. This feature can be useful for giving an easily identifiable or task related name to the EVM coin.
To edit the EVM name:
- In the Coin Management screen, find the EVM coin you want to edit, or type EVM in the filter.
- In the EVM coin card, select the edit icon.
- All editable fields, including the Name become active.
- Update the name.
- Select Save changes.
