Clarify the current situation wrt key derivation algorithms
@@ -222,7 +222,7 @@ has an `algorithm` property that indicates how to generate the key from
the passphrase. Other properties of the `passphrase` property are
defined by the `algorithm` specified.
-For the `m.pbkdf2` algorithm, the `passphrase` property has the
+Currently, the only algorithm defined is `m.pbkdf2`. For the `m.pbkdf2` algorithm, the `passphrase` property has the
following properties:
| Parameter | Type | Description |
