Data Action API 400 on custom field validation via Terraform v1.15.4

Is it possible to bypass the strict JSON schema validation for custom fields in a Data Action when deploying via Terraform?

Environment: US-1 Production. Provider v1.15.4.

Attempting to apply a genesyscloud_data_action resource. The configuration includes a custom input field with a complex nested object structure. The apply fails immediately with HTTP 400 Bad Request.

Error log:

Error: POST /api/v2/analytics/data-actions: 400 Bad Request
{"errors":[{"code":"invalid_body","message":"Invalid JSON in input definition","parameter":"inputs[0].definition"}]}

The HCL block:

resource "genesyscloud_data_action" "test_action" {
 name = "Custom_Validation_Test"
 description = "Test nested input"
 
 inputs {
 name = "payload"
 type = "object"
 definition = jsonencode({
 type = "object"
 properties = {
 details = {
 type = "object"
 properties = {
 ref = {
 type = "string"
 }
 }
 }
 }
 })
 }
}

Manual API call using Postman with identical JSON body succeeds. Terraform provider seems to be sanitizing or altering the payload before sending. Is this a known limitation with nested objects in the provider? Or is there a syntax adjustment required for the definition attribute?