diff --git a/README.md b/README.md
index bb1ecd1..d27701b 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ The Operator returns a tuple `Tuple[('embedding', numpy.ndarray)]` containing fo
 - feature_vector:
   - the embedding of the image
   - data type: `numpy.ndarray`
-
+  - shape: (dim,)
 ## Requirements
 
 You can get the required python package by [requirements.txt](./requirements.txt).