diff --git a/website/docs/usage/processing-pipelines.md b/website/docs/usage/processing-pipelines.md
index 9e8e87239..836bdac67 100644
--- a/website/docs/usage/processing-pipelines.md
+++ b/website/docs/usage/processing-pipelines.md
@@ -1547,24 +1547,33 @@ to `Doc.user_span_hooks` and `Doc.user_token_hooks`.
 
 | Name               | Customizes                                                                                                                                                                                                              |
 | ------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| `user_hooks`       | [`Doc.vector`](/api/doc#vector), [`Doc.has_vector`](/api/doc#has_vector), [`Doc.vector_norm`](/api/doc#vector_norm), [`Doc.sents`](/api/doc#sents)                                                                      |
+| `user_hooks`       | [`Doc.similarity`](/api/doc#similarity), [`Doc.vector`](/api/doc#vector), [`Doc.has_vector`](/api/doc#has_vector), [`Doc.vector_norm`](/api/doc#vector_norm), [`Doc.sents`](/api/doc#sents)                                                                      |
 | `user_token_hooks` | [`Token.similarity`](/api/token#similarity), [`Token.vector`](/api/token#vector), [`Token.has_vector`](/api/token#has_vector), [`Token.vector_norm`](/api/token#vector_norm), [`Token.conjuncts`](/api/token#conjuncts) |
 | `user_span_hooks`  | [`Span.similarity`](/api/span#similarity), [`Span.vector`](/api/span#vector), [`Span.has_vector`](/api/span#has_vector), [`Span.vector_norm`](/api/span#vector_norm), [`Span.root`](/api/span#root)                     |
 
 ```python
 ### Add custom similarity hooks
+from spacy.language import Language
+
+
 class SimilarityModel:
-    def __init__(self, model):
-        self._model = model
+    def __init__(self, name: str, index: int):
+        self.name = name
+        self.index = index
 
     def __call__(self, doc):
         doc.user_hooks["similarity"] = self.similarity
         doc.user_span_hooks["similarity"] = self.similarity
         doc.user_token_hooks["similarity"] = self.similarity
+        return doc
 
     def similarity(self, obj1, obj2):
-        y = self._model([obj1.vector, obj2.vector])
-        return float(y[0])
+        return obj1.vector[self.index] + obj2.vector[self.index]
+
+
+@Language.factory("similarity_component", default_config={"index": 0})
+def create_similarity_component(nlp, name, index: int):
+    return SimilarityModel(name, index)
 ```
 
 ## Developing plugins and wrappers {#plugins}