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Authorizations

BIZ-API-KEY
string
header
required

The API key. For more details, refer to API key.

In the API playground, enter your API secret, and your API key will be accordingly calculated.

Body

application/json

The request body for evaluating Billing Center usage.

The information for evaluating Billing Center usage.

request_id
string
required

The request ID that is used to track a transaction request. The request ID is provided by you and must be unique within your organization.

Example:

"f47ac10b-58cc-4372-a567-0e02b2c3d479"

estimated_fee_amount
string
required

The estimated transaction fee required for this transfer, before applying any Billing Center rules.

Example:

"0.0021"

from_address
string
required

The blockchain address that initiates the transfer.

Example:

"0x1234567890abcdef1234567890abcdef12345678"

from_wallet_id
string<uuid>
required

The wallet ID.

Example:

"f47ac10b-58cc-4372-a567-0e02b2c3d479"

amount
string

Applicable to transfer requests only. The amount of tokens to be transferred in this request.

Example:

"100.5"

token_id
string

Applicable to transfer requests only. The token ID of the asset to be transferred. You can retrieve available token IDs by calling List enabled tokens.

Example:

"ETH_USDT"

fee_token_id
string

The token ID used to pay the gas fee for the main transaction. You can retrieve available token IDs by calling List enabled tokens.

Example:

"ETH"

auto_fuel
enum<string>

Whether Billing Center pays the on-chain transaction fee for this transaction, and under what condition.

On-chain fees are charged in a chain's gas token, which is usually not the token you are sending. Without Billing Center, the source address must hold that gas token or the transaction fails. When Billing Center covers the fee, the source address does not need to hold any gas token.

For more details, refer to Billing Center.

Accepted values

  • ProActiveAutoFuel: Always have Billing Center pay the fee, without touching the gas token in the source address.
  • PassiveAutoFuel: Use the gas token in the source address when it is sufficient; otherwise have Billing Center pay the fee.
  • UsePortalPreference: Follow the per-chain sponsorship rules configured on Cobo Portal, under Billing Center > Settings.
  • DisableAutoFuel: Never use Billing Center. The transaction pays its fee from the source address and fails if the balance is insufficient.

If this parameter is not specified, it defaults to UsePortalPreference.

Support and limitations

  • Applies to transactions from MPC Wallets and Custodial Wallets (Web3 Wallets) on EVM-compatible chains, TRON, Solana, and Tempo. Other chains, such as BTC, are not supported, and the source address must hold the fee itself.
  • TRON, Solana, and Tempo do not support PassiveAutoFuel due to their fee delegation mechanisms.
  • The per-chain sponsorship rules on Cobo Portal apply only to API transactions that pass UsePortalPreference. They do not affect transfers initiated from the Cobo Portal interface.
Available options:
PassiveAutoFuel,
ProActiveAutoFuel,
UsePortalPreference,
DisableAutoFuel
Example:

"PassiveAutoFuel"

Response

The request was successful.

The fee station evaluation result for the transfer request.

token_id
string
required

The token used to pay the gas fee for this specific transaction. You can retrieve the IDs of all supported tokens by calling List enabled tokens.

Example:

"ETH"

balance
string
required

The current token balance available in Billing Center.

Example:

"0.0021"

gas_station_type
enum<string>
required

The Billing Center mode used for automatic gas payment:

  • FeeStation: The user uses their own Billing Center balance to cover the gas fee.
  • CoboOperationStation: Cobo covers the gas fee on behalf of the user.
Available options:
FeeStation,
CoboOperationStation
Example:

"CoboOperationStation"

is_fee_station_applicable
boolean
required

Indicates whether Billing Center is applied for this transfer request.

Example:

true

is_balance_sufficient
boolean
required

If Billing Center is used, indicates whether its balance is sufficient to cover the required gas fee.

Example:

false

total_fee_amount
string
required

The total gas amount required for this transfer request.

Example:

"0.0021"

is_sponsor_applicable
boolean
required

Indicates whether USD stablecoin sponsorship is applied when the Billing Center balance is insufficient.

Example:

true

sponsored_fee_amount
string
required

The amount of gas fee sponsored by USD stablecoin when applicable.

Example:

"0.0021"

sponsored_token_id
string

The token ID used to sponsor the gas fee.

Example:

"ETH_USDT"