diff --git a/status-whisper-usage-spec.md b/status-whisper-usage-spec.md
index 72b8e58..b60b576 100644
--- a/status-whisper-usage-spec.md
+++ b/status-whisper-usage-spec.md
@@ -218,3 +218,7 @@ It's recommended to return messages from newest to oldest. To move further back
 
 **Returns**:
 `Boolean` - returns `true` if the request was sent.
+
+The above `topics` is then converted into a bloom filter and then and sent to the Mailserver.
+
+<!-- TODO: Clarify actual request with bloom filter to mailserver -->