Signing endpoints
Circle provides four signing endpoints for developer-controlled wallets. You call one endpoint per request, depending on what you are signing:- Sign transaction: Sign a raw transaction for broadcasting to a blockchain.
- Sign message: Sign an arbitrary message using EIP-191 (EVM) or a plain message (NEAR).
- Sign typed data: Sign structured data using EIP-712 (EVM only).
- Sign delegate action: Sign a delegate action to authorize another account to act on your behalf (NEAR only).
The signing flow
To sign and broadcast a transaction:- Build the raw transaction in your application, including nonce, gas parameters, and any blockchain-specific encoding. For example, NEAR requires Borsh serialization before signing.
- Call the Sign transaction endpoint. Circle signs the transaction and returns the signed payload.
- Broadcast the signed transaction to a node provider of your choice.
Signing for EVM wallets
For blockchains in the Supported Blockchains Other EVM category, create a wallet usingblockchain: EVM for mainnet or
blockchain: EVM-TESTNET for testing. These are virtual blockchain parameters
not tied to a specific blockchain. You specify the target blockchain using
chainId at signing time. For a list of supported testnet chain IDs, see
EVM Testnet Chain IDs for Signing.