Here is what the header should look like when listing an inscription for sale:
{
"rootTx": "",
"action": "sell",
"timestamp": number,
"data": {
},
"signature": "SHA3-512 hash of signature of rootTx + action + timestamp + data"
}
This is what the data field should look like:
"data": {
"price": number, // The price in satoshis
"payTo": "" // The address that the payment must be given to
}