diff --git a/src/Tahoe/Announcement.hs b/src/Tahoe/Announcement.hs
index 6fb69a187f3e708ce2c5155c52125d871a69d6d5..3ad916d4e9c2f7eacb11b4fe707717d996f801ef 100644
--- a/src/Tahoe/Announcement.hs
+++ b/src/Tahoe/Announcement.hs
@@ -107,6 +107,11 @@ greatBlackSwampURIs =
 {- | Parse a Tahoe-LAFS fURL.  For example:
 
  pb://gnuer2axzoq3ggnn7gjoybmfqsjvaow3@tcp:localhost:46185/sxytycucj5eeunlx6modfazq5byp2hpb
+
+  This *does not* parse NURLs which are the expected way that GBS locations
+  will be communicated.
+
+  See https://whetstone.private.storage/privatestorage/gbs-downloader/-/issues/6
 -}
 parseURI' :: T.Text -> Maybe URI
 parseURI' = Network.URI.parseURI . T.unpack . Data.Text.replace "tcp:" ""