diff --git a/v3.md b/v3.md
index d89c4875..58887aed 100644
--- a/v3.md
+++ b/v3.md
@@ -34,3 +34,5 @@ Copy protocol support (this potentially ties in with text/binary protocol)
 ValueReader / msgReader cleanup
 
 Make easier / possible to mock Conn or ConnPool (https://github.com/jackc/pgx/pull/162)
+
+Every field that should not be set by user should be replaced by accessor method (e.g. Conn.PID, Conn.SecretKey)