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Get USDC Authorization Message (EVM only)

Gets the USDC authorization message to be signed by the customer for dual-source payments. The signed message allows the customer’s USDC to be used alongside credit card payment.

This is only necessary for EVM chains when using customer USDC + credit card payment.

Authentication

x-coinflow-auth-session-keystring

The session key generated for the end user - see https://docs.coinflow.cash/api-reference/api-reference/authentication/get-session-key

OR
x-coinflow-auth-walletstring

The web3 wallet of the end user - see https://docs.coinflow.cash/api-reference/api-reference/authentication/get-session-key

x-coinflow-auth-blockchainstring

The blockchain associated with the end user - see https://docs.coinflow.cash/api-reference/api-reference/authentication/get-session-key

Request

This endpoint expects an object.
amountobjectRequired
paymentIdstringOptional
Optional payment ID for generating unique nonce

Response

Ok
messagestring

EIP-712 message to sign

messageDataobject
Structured message data for transparency