curl --request POST \
  --url https://api.privy.io/v1/wallets/{wallet_id}/rpc \
  --header 'Authorization: Basic <encoded-value>' \
  --header 'Content-Type: application/json' \
  --header 'privy-app-id: <privy-app-id>' \
  --data '{
  "method": "eth_signTypedData_v4",
  "params": {
    "typed_data": {
      "types": {
        "EIP712Domain": [
          { "name": "name", "type": "string" },
          { "name": "version", "type": "string" },
          { "name": "chainId", "type": "uint160" },
          { "name": "verifyingContract", "type": "address" }
        ],
        "Person": [
          { "name": "name", "type": "string" },
          { "name": "wallet", "type": "address" }
        ],
        "Mail": [
          { "name": "from", "type": "Person" },
          { "name": "to", "type": "Person" },
          { "name": "contents", "type": "string" }
        ]
      },
      "message": {
        "from": {
          "name": "Alice",
          "wallet": "0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826"
        },
        "to": {
          "name": "Bob",
          "wallet": "0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB"
        },
        "contents": "Hello, Bob!"
      },
      "primary_type": "Mail",
      "domain": {
        "name": "DApp Mail",
        "version": "1",
        "chainId": "0x3e8",
        "verifyingContract": "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC"
      }
    }
  }
}'

{
  "method": "eth_signTypedData_v4",
  "data": {
    "signature": "0x1754782aea15e96189c3a85a7b7ac2f6339f6f4f3b29b1d3200a4c9907ef53e4776a84387583896b0a074cbc6de1a1c2a1eb53aba199da6ada8c99b0266171c41b",
    "encoding": "hex"
  }
}