diff --git a/CLAUDE.md b/CLAUDE.md
index 3c727ab..f9bf81c 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -16,6 +16,7 @@ This is a ComfyUI extension that adds a server-side notes sidebar for managing m
 
 ### Frontend (JavaScript)
 - **Extension Module**: `js/extension.js` - ComfyUI extension integration
+- **NotesStore Class**: Event-driven state management using EventTarget pattern
 - **NotesSidebar Class**: Main UI component managing tabs, content area, and user interactions
 - **Styling**: `js/notes-sidebar.css` - Complete UI styling for dark theme integration
 
@@ -25,10 +26,11 @@ This is a ComfyUI extension that adds a server-side notes sidebar for managing m
 2. **File Management**: Notes stored as markdown files with automatic directory creation
 3. **UI Architecture**: Tab-based interface with content area and action buttons
 4. **Extension Registration**: Properly registers with ComfyUI's extension manager as a sidebar tab
-5. **State Management**: Three Maps track content state:
+5. **State Management**: Centralized state using NotesStore class with EventTarget pattern:
    - `noteContent`: Current content for each note (including unsaved)
    - `savedContent`: Last saved content from server
    - `unsavedChanges`: Boolean flag for each note's modification state
+   - Event-driven updates automatically sync UI components
 
 ## API Endpoints
 
@@ -66,6 +68,13 @@ The extension exposes these REST endpoints:
 - Save operation clears unsaved state and updates saved content reference
 - Delete/rename operations properly clean up tracking maps
 
+### Key Architectural Patterns
+- **State Management**: Uses EventTarget pattern for reactive state updates
+- **File I/O**: Synchronous file operations in Python with proper error handling
+- **API Design**: RESTful endpoints with JSON responses and consistent error handling
+- **UI Updates**: Event-driven architecture prevents manual DOM manipulation
+- **Extension Integration**: Follows ComfyUI's extension patterns (NODE_CLASS_MAPPINGS, registerExtension)
+
 ## Development Commands
 
 ### Installation & Setup
@@ -84,8 +93,8 @@ No automated tests defined. Manual testing workflow:
 1. Modify Python code in `__init__.py` for backend changes
 2. Modify JavaScript in `js/extension.js` for frontend changes
 3. Update CSS in `js/notes-sidebar.css` for styling changes
-4. Restart ComfyUI to reload the extension (required for Python changes)
-5. Refresh browser for JavaScript/CSS changes
+4. **Python changes**: Restart ComfyUI completely to reload the extension
+5. **JavaScript/CSS changes**: Browser refresh is sufficient
 
 ### File Structure
 - `notes/` - Storage directory for markdown notes (auto-created)
diff --git a/js/extension.js b/js/extension.js
index b911535..a802f3e 100644
--- a/js/extension.js
+++ b/js/extension.js
@@ -434,8 +434,21 @@ class NotesSidebar {
     }
 
     async createNewNote() {
-        const noteName = prompt('Enter note name:');
-        if (!noteName) return;
+        let noteName;
+
+        // Keep asking for a name until user cancels or enters a unique name
+        while (true) {
+            noteName = prompt('Enter note name:');
+            if (!noteName) return; // User cancelled
+
+            // Check if note name already exists
+            if (this.notes.includes(noteName)) {
+                alert('A note with this name already exists!');
+                continue; // Ask again
+            }
+
+            break; // Valid unique name
+        }
 
         try {
             const response = await fetch(`/notes_sidebar/note/${encodeURIComponent(noteName)}`, {