Data Action returns undefined for nested JSON path mapping

Trying to extract a value from a nested object in a Data Action. The external API returns valid JSON, but the output variable is always undefined. The path syntax looks right based on the docs. Here is the mapping config:

{
 "output": {
 "status": "$.data.response.status"
 }
}

The response body has data as an object containing response. Am I missing a step or is the parser strict about object vs array types?