Architect Data Action REST response mapping fails on nested array index

Architect & Flows
1

400 Bad Request: “Failed to parse JSON response for variable mapping. Path ‘items[0].id’ not found in response body.” The Data Action successfully calls the external endpoint https://api.vendor.com/v1/inventory with a 200 OK status. The raw response contains a JSON object with an items array. However, the mapping configuration in the Architect flow fails when attempting to extract items[0].id into a flow variable. I am using the standard REST Data Action type. The response payload is valid JSON. The issue appears to be that the mapping engine does not support array indexing syntax in the JSONPath expression field. I have tried using items[0], items[0].id, and $.items[0].id in the mapping definition. All attempts result in the same 400 error during flow validation. The documentation for Data Action mappings is sparse regarding complex JSON structures. Is there a supported syntax for extracting values from nested arrays in the response mapping JSON, or must I flatten the response in the external service before returning it to Genesys Cloud? I need to map the first item’s ID to a string variable without modifying the upstream API response.

2

This seems like a standard schema definition issue within the Architect Data Action. When you map a nested array index directly in the path string, the JSON parser often fails if it expects a specific object structure or if the array is empty. The REST Data Action returns a raw string, and the mapping engine needs explicit guidance on how to treat that string as a structured object before you can index into it.

I have seen this frequently when integrating external inventory APIs. The fix is usually not in the mapping path itself, but in how you define the Response Schema in the Data Action configuration. You need to explicitly define the items array schema so the parser knows the structure exists before attempting to access index [0].

Here is the step-by-step solution:

  1. Open your Data Action in Architect.
  2. Navigate to the Response tab.
  3. Ensure the Response Format is set to JSON.
  4. Click Edit Schema (or the pencil icon) for the response body.
  5. Define the schema explicitly. Do not rely on auto-detection for nested arrays. Your schema should look like this:
{
 "type": "object",
 "properties": {
 "items": {
 "type": "array",
 "items": {
 "type": "object",
 "properties": {
 "id": { "type": "string" },
 "name": { "type": "string" },
 "stock": { "type": "integer" }
 }
 }
 }
 }
}
  1. Save the schema.
  2. In the Variable Mapping section, update your path. Instead of items[0].id, try mapping the entire items array to a variable first, then use a Set Variable action with an expression like ${inventoryItems[0].id} if needed later in the flow. Alternatively, keep the mapping in the Data Action but ensure the schema is saved.

This forces the parser to validate the structure against your defined schema, which often resolves the “path not found” error even when the raw JSON is valid. The parser needs to know items is an array of objects, not just a generic object.