For anyone else trying to figure this out, I used the json response from an item in the curatorRuleList object from the GET /curator/v2/collections/{collection}/profiles/{profile}/curator endpoint to come up with the following json to send. It seems to do the trick.
{
"name": "From api",
"label": "DEFAULT",
"enabled": true,
"trigger":
{
"type": "And",
"triggers": [
{
"type": "Or",
"triggers": [
{
"type": "QueryRegularExpression",
"triggerPattern": "^cow.*$"
}
]
}
]
},
"actions": [
{
"type": "DisplayUrlAdvert",
"titleHtml": "Cows on a farm",
"displayUrl": "farmers.com",
"linkUrl": "farmers.com",
"descriptionHtml": "Cows are cool",
"additionalProperties": {},
"category": "",
"removeCollectionUrl": true
}
]
}