What system are you trying to send thew webhook to? They very likely offer some kind of documentation about what they expect to see in a webhook. Since it isn't Quick Base you are sending to I cannot give you a full answer other than you need to at least format it like JSON. You are going to need more than just the options you want to send most likely, but again this will be in the documentation of whatever you are sending this to.
The error message it gave you is a hint to how to format this.
This is simple JSON and might work.
{
"param1": [Field you want to send data from],
"param2": "Jim",
"param3": "csv"
}