diff --git a/doc/proto_v0.txt b/doc/proto_v0.txt
index 78bbc0696..b23fef9e1 100644
--- a/doc/proto_v0.txt
+++ b/doc/proto_v0.txt
@@ -180,7 +180,7 @@ Encrypted frames:
 
 {
   v: 0,
-  w: <32+32+32+N bytes payload>
+  w: "<32+32+32+N bytes payload>"
 }
 
 Encrypted frames are encrypted containers for link message records like LRCR.