diff --git a/conductor/tracks/undo_redo_history_20260311/plan.md b/conductor/tracks/undo_redo_history_20260311/plan.md
index eebf202..15d18e7 100644
--- a/conductor/tracks/undo_redo_history_20260311/plan.md
+++ b/conductor/tracks/undo_redo_history_20260311/plan.md
@@ -2,11 +2,11 @@
 
 This plan implements a robust undo/redo system focusing on text inputs, control states, and discussion structure.
 
-## Phase 1: History Core Logic & State Management
+## Phase 1: History Core Logic & State Management [checkpoint: 9a699a5]
 - [x] Task: Design and implement a generic `HistoryManager` class to handle undo/redo stacks and state snapshots. 7743b15
 - [x] Task: Write failing tests for the `HistoryManager` core logic, including capacity limits and basic undo/redo functionality. 7743b15
 - [x] Task: Implement `HistoryManager` to pass tests, ensuring it correctly manages a fixed stack of 50-100 actions. 7743b15
-- [ ] Task: Conductor - User Manual Verification 'Phase 1: History Core Logic & State Management' (Protocol in workflow.md)
+- [x] Task: Conductor - User Manual Verification 'Phase 1: History Core Logic & State Management' (Protocol in workflow.md) 9a699a5
 
 ## Phase 2: Text Input & Control Undo/Redo
 - [ ] Task: Integrate `HistoryManager` with `src/gui_2.py` for system prompt and discussion entry text fields.