Address PR review comments

- Update .env.example to use claude-sonnet-4-5 model
- Remove "Always check memory first" from system prompts
- Add warning to clear_all_memory() about demonstration purposes
- Add path validation assertion in _delete() for safety
- Add notebook cell warning about memory clearing
- Clarify "Pattern Stored" section to show what Claude learns

All changes verified against official memory tool documentation.

tool_use/.env.example

@@ -11,4 +11,4 @@ ANTHROPIC_API_KEY=your_api_key_here
 # - claude-opus-4-1-20250805
 # - claude-sonnet-4-5-20250929
 
-ANTHROPIC_MODEL=claude-sonnet-4-20250514
+ANTHROPIC_MODEL=claude-sonnet-4-5

tool_use/memory_demo/code_review_demo.py

@@ -82,10 +82,9 @@ class CodeReviewAssistant:
         return """You are an expert code reviewer focused on finding bugs and suggesting improvements.
 
 MEMORY PROTOCOL:
-1. ALWAYS check your /memories directory FIRST using the memory tool
-2. Look for relevant debugging patterns or insights from previous reviews
-3. When you find a bug or pattern, update your memory with what you learned
-4. Keep your memory organized - use descriptive file names and clear content
+1. Check your /memories directory for relevant debugging patterns or insights
+2. When you find a bug or pattern, update your memory with what you learned
+3. Keep your memory organized - use descriptive file names and clear content
 
 When reviewing code:
 - Identify bugs, security issues, and code quality problems

tool_use/memory_tool.py

@@ -289,6 +289,16 @@ class MemoryToolHandler:
 
         full_path = self._validate_path(path)
 
+        # Verify the path is within /memories to prevent accidental deletion outside the memory directory
+        # This provides an additional safety check beyond _validate_path
+        try:
+            full_path.relative_to(self.memory_root.resolve())
+        except ValueError:
+            return {
+                "error": f"Invalid operation: Path '{path}' is not within /memories directory. "
+                "Only paths within /memories can be deleted."
+            }
+
         if not full_path.exists():
             return {"error": f"Path not found: {path}"}
 
@@ -339,6 +349,11 @@ class MemoryToolHandler:
         """
         Clear all memory files (useful for testing or starting fresh).
 
+        ⚠️ WARNING: This method is for demonstration and testing purposes only.
+        In production, you should carefully consider whether you need to delete
+        all memory files, as this will permanently remove all learned patterns
+        and stored knowledge. Consider using selective deletion instead.
+
         Returns:
             Dict with success message
         """