API Reference

Create a challenge to sign transaction

posthttps://api.circle.com/v1/w3s/user/sign/transaction

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Generate a challenge for signing the transaction from a specific user-controlled wallet.

NOTE: This endpoint supports the following blockchains: SOL, SOL-DEVNET, EVM, EVM-TESTNET. Each chain defines its own standard. For more details, see Signing APIs.

Header parameters
X-User-Token
string
Required

Unique system generated JWT session token for specific user.

Body parameters
walletId
string
Required

System-generated unique identifier of the resource.

rawTransaction
string

Raw transaction string that needs to be signed. Excluded with transaction. Required without transaction. Required to be base64 encoded for NEAR, Solana chains. Required to be hex encoded for EVM chains.

transaction
string

Transaction object in JSON that needs to be signed. Excluded with rawTransaction. Required without rawTransaction.

NOTE: This field is only supported by EVM chains.

memo
string

The human readable explanation for this sign action. Useful for presenting with extra information.

Response
RequestChoose a language
ResponseChoose an example
1{
2  "data": {
3    "challengeId": "c4d1da72-111e-4d52-bdbf-2e74a2d803d5"
4  }
5}
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