+ **index.decrypt**
+
+ **[STORED IN DATABASE]**
+ When indexing an encrypted e-mail message, if this variable is
+ set to ``true``, notmuch will try to decrypt the message and
+ index the cleartext, stashing a copy of any discovered session
+ keys for the message. If ``auto``, it will try to index the
+ cleartext if a stashed session key is already known for the message
+ (e.g. from a previous copy), but will not try to access your
+ secret keys. Use ``false`` to avoid decrypting even when a
+ stashed session key is already present.
+
+ Be aware that the notmuch index is likely sufficient to
+ reconstruct the cleartext of the message itself, so please
+ ensure that the notmuch message index is adequately protected.
+ DO NOT USE ``index.decrypt=true`` without considering the
+ security of your index.
+
+ Default: ``auto``.
+