raise TypeError if you attempt to get the tag attribute on a decrypt
* To support this the _AEADCipherContext in base.py now needs to be
aware of whether it is encrypting/decrypting
diff --git a/docs/hazmat/primitives/symmetric-encryption.rst b/docs/hazmat/primitives/symmetric-encryption.rst
index d123d15..f35357d 100644
--- a/docs/hazmat/primitives/symmetric-encryption.rst
+++ b/docs/hazmat/primitives/symmetric-encryption.rst
@@ -139,6 +139,7 @@
:return bytes: Returns the tag value as bytes.
:raises: :class:`~cryptography.exceptions.NotYetFinalized` if called
before the context is finalized.
+ :raises TypeError: If called on a decryption context.
.. _symmetric-encryption-algorithms: