Data Action mapping nested JSON array to Architect variables

Architect & Flows
1

Hey folks,

Trying to build a Data Action that calls an external REST endpoint and maps the response back to Architect variables. The API returns a JSON object with a nested array, and I’m hitting a wall on how to reference those items in the mapping step.

Here’s the response structure I’m getting back from the GET request:

{
 "status": "success",
 "data": {
 "customerId": "12345",
 "preferences": [
 {
 "type": "email",
 "value": "john@example.com"
 },
 {
 "type": "phone",
 "value": "555-0199"
 }
 ]
 }
}

The Data Action runs fine and I can see the full JSON payload in the debug log. I can map data.customerId to a string variable without issue. But when I try to map data.preferences[0].value to another variable, the mapping fails silently or just returns null.

I’ve tried using dot notation, bracket notation, and even flattening the JSON beforehand with a script task, but nothing seems to stick in the Data Action output mapping.

Is there a specific syntax for accessing array elements in the Data Action JSON mapping schema? Or do I need to iterate through the array in a separate step before mapping?

Here’s the relevant part of my Data Action JSON definition:

{
 "request": {
 "method": "GET",
 "url": "https://api.internal.com/v1/customer/{{customer_id}}"
 },
 "output": {
 "customer_id": "$.data.customerId",
 "primary_contact": "$.data.preferences[0].value"
 }
}

Any pointers would be appreciated.