diff --git a/backend/utils/assets_client.py b/backend/utils/assets_client.py
index 713772a..ca306da 100644
--- a/backend/utils/assets_client.py
+++ b/backend/utils/assets_client.py
@@ -66,15 +66,23 @@ def _do_request(action: str, body_dict: dict) -> dict:
     try:
         resp = service.json(action, {}, body)
     except Exception as e:
-        error_str = str(e)
+        # SDK raises Exception(resp.text.encode("utf-8")) on non-200;
+        # str(e) becomes b'...' which isn't valid JSON. Decode it first.
+        raw = e.args[0] if e.args else ''
+        error_str = raw.decode('utf-8') if isinstance(raw, bytes) else str(raw)
+        logger.warning('Assets API %s raw error: %s', action, error_str)
         try:
             error_data = json.loads(error_str)
+            err_meta = error_data.get('ResponseMetadata', {}).get('Error', {})
+            if err_meta:
+                raise AssetsAPIError(err_meta.get('Code', 'Unknown'), err_meta.get('Message', error_str))
             err = error_data.get('error', {})
             raise AssetsAPIError(err.get('code', 'Unknown'), err.get('message', error_str))
         except (json.JSONDecodeError, AssetsAPIError):
             raise
         except Exception:
-            raise AssetsAPIError('RequestError', error_str)
+            pass
+        raise AssetsAPIError('RequestError', error_str or 'Empty response from API')
 
     data = json.loads(resp) if isinstance(resp, str) else resp