diff --git a/CHANGELOG.md b/CHANGELOG.md
index 98f1e39b1..1400aa457 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,9 @@ Format based on [Keep a Changelog](https://keepachangelog.com/).
 ### Added
 - `ticket team` command and `--team` filter — comma-separated team assignment for tickets (server, client, joint, content)
 
+### Changed
+- `start-sprint` skill now requires plan mode — agent must create and get approval for a concrete sprint plan before starting implementation
+
 ### Fixed
 - `start-sprint` skill uses `git rev-parse --show-toplevel` for worktree-safe absolute paths — fixes "No such file or directory" errors on team branches