diff --git a/python/pydantic_core/__init__.py b/python/pydantic_core/__init__.py
index 791de9d92..2de8b301d 100644
--- a/python/pydantic_core/__init__.py
+++ b/python/pydantic_core/__init__.py
@@ -89,6 +89,11 @@ class ErrorDetails(_TypedDict):
     Values which are required to render the error message, and could hence be useful in rendering custom error messages.
     Also useful for passing custom error data forward.
     """
+    url: _NotRequired[str]
+    """
+    The documentation URL giving information about the error. No URL is available if
+    a [`PydanticCustomError`][pydantic_core.PydanticCustomError] is used.
+    """
 
 
 class InitErrorDetails(_TypedDict):