How to: Sign a Message

Sign a plain text message or EIP-712 typed data with your agent wallet.

Sign messages or EIP-712 typed data with your agent wallet. Signing is commonly used to prove wallet ownership or authorize offchain actions.

Prerequisites

Before you begin, ensure you have:

• Installed Node.js v20.18.2 or later.

• Installed Circle CLI:

  npm install -g @circle-fin/cli
  

• Authenticated your agent wallet.

Sign a message

Run circle wallet sign with your message and wallet details. Each command returns a signature (0xabcdef1234...):

# Sign a plain text message
circle wallet sign message "hello world" --address 0xYourWalletAddress --chain BASE

# Sign a hex-encoded message
circle wallet sign message "0xdeadbeef" --hex --address 0xYourWalletAddress --chain BASE

# Sign EIP-712 typed data (EVM only)
circle wallet sign typed-data \
  '{"types":{...},"primaryType":"Mail","domain":{...},"message":{...}}' \
  --address 0xYourWalletAddress \
  --chain BASE

Typed data signing is supported on EVM blockchains only.

See the CLI Command Reference for full syntax and options.