curl --request POST \
  --url https://api.example.com/api/v1/platform/tenants/{tenant_id}/callbacks/endpoints/{endpoint_id}/subscriptions \
  --header 'Content-Type: application/json' \
  --header 'X-Api-Id: <x-api-id>' \
  --header 'X-Api-Nonce: <x-api-nonce>' \
  --header 'X-Api-Signature: <api-key>' \
  --header 'X-Api-Timestamp: <x-api-timestamp>' \
  --data '
{
  "event_type": "command.completed",
  "status": "ACTIVE"
}
'

{
  "subscription_id": "callback_subscription_001",
  "tenant_id": "tenant_001",
  "endpoint_id": "callback_endpoint_001",
  "event_type": "command.completed",
  "status": "ACTIVE",
  "request_id": "req-001"
}