diff --git a/docs/source/interface.rst b/docs/source/interface.rst
index 0ec7d3910c1fe7a70d769f67324dac3bb2eb8b98..d899f5451e189313737baeccaa11ff82fd9049db 100644
--- a/docs/source/interface.rst
+++ b/docs/source/interface.rst
@@ -32,11 +32,15 @@ If the voucher is not known then the response is **NOT FOUND**.
 For any voucher which has previously been submitted,
 the response is **OK** with an ``application/json`` content-type response body like::
 
-  {"value": <string>, "created": <iso8601 timestamp>, "redeemed": bool, "version": 1}
+  {"value": <string>, "created": <iso8601 timestamp>, "redeemed": <boolean>, "token-count": <number>, "version": 1}
 
 The ``value`` property merely indicates the voucher which was requested.
 The ``created`` property indicates when the voucher was first added to the node.
 The ``redeemed`` property indicates whether or not the voucher has successfully been redeemed with a payment server yet.
+The ``token-count`` property gives the number of blinded token signatures the client received in exchange for redemption of the voucher
+(each blinded token signature can be used to construct a one ZKAP),
+if it has been redeemed.
+If it has not been redeemed then it is ``null``.
 
 The ``version`` property indicates the semantic version of the data being returned.
 When properties are removed or the meaning of a property is changed,
diff --git a/src/_zkapauthorizer/model.py b/src/_zkapauthorizer/model.py
index 331ec04a990f526cd651abd15e3e3c0cb2a14739..6be37722c61955255d154fe98fe732d9dd7923cb 100644
--- a/src/_zkapauthorizer/model.py
+++ b/src/_zkapauthorizer/model.py
@@ -464,7 +464,7 @@ class Voucher(object):
             number=values[u"number"],
             created=None if values[u"created"] is None else parse_datetime(values[u"created"]),
             redeemed=values[u"redeemed"],
-            token_count=values[u"token_count"],
+            token_count=values[u"token-count"],
         )
 
 
@@ -481,6 +481,6 @@ class Voucher(object):
             u"number": self.number,
             u"created": None if self.created is None else self.created.isoformat(),
             u"redeemed": self.redeemed,
-            u"token_count": self.token_count,
+            u"token-count": self.token_count,
             u"version": 1,
         }