diff --git a/doc/drafts/k2v-spec.md b/doc/drafts/k2v-spec.md
index 706d636c..362df6c4 100644
--- a/doc/drafts/k2v-spec.md
+++ b/doc/drafts/k2v-spec.md
@@ -385,7 +385,8 @@ The response consists in a JSON object that repeats the parameters of the query
 
 The listing starts at partition key `start`, or if not specified at the
 smallest partition key that exists.  It returns partition keys in increasing
-order and stops when either of the following conditions is met:
+order, or decreasing order if `reverse` is set to `true`,
+and stops when either of the following conditions is met:
 
 1. if `end` is specfied, the partition key `end` is reached or surpassed (if it
    is reached exactly, it is not included in the result)
@@ -400,6 +401,11 @@ the first partition key that couldn't be listed due to the limit. In the first
 case (if the listing stopped because of the `end` parameter), `more` is not set
 and the `nextStart` key is not specified.
 
+Note that if `reverse` is set to `true`, `start` is the highest key
+(in lexicographical order) for which values are returned.
+This means that if an `end` is specified, it must be smaller than `start`,
+otherwise no values will be returned.
+
 Example query:
 
 ```