diff --git a/src/core/error.ts b/src/core/error.ts
index 723a15dd1..6451e6a63 100644
--- a/src/core/error.ts
+++ b/src/core/error.ts
@@ -66,7 +66,7 @@ export class APIError<
       return new APIConnectionError({ message, cause: castToError(errorResponse) });
     }
 
-    const error = (errorResponse as Record<string, any>)?.['error'];
+    const error = (errorResponse as Record<string, any>)?.['error'] ?? errorResponse;
 
     if (status === 400) {
       return new BadRequestError(status, error, message, headers);