CLAUDE.md: Update.

1 files changed, 55 insertions, 3 deletions

diff --git a/CLAUDE.md b/CLAUDE.md
index 0ad2606..4a470ad 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -39,6 +39,14 @@ The application uses a type-safe command architecture with Zig unions and enums:
 - **`InputSource`**: Manages input redirection from files with line-by-line processing
 - **`OutputCapture`**: Buffers command output for redirection to files
 
+### Modular Command Architecture
+The project now uses a fully modularized command architecture where each DOS command is implemented in its own file:
+
+- **`src/cmd/`**: Directory containing individual command implementations
+- **Command Pattern**: Each command implements an `eval()` method with consistent signature
+- **Type Safety**: Commands are strongly typed Zig structs with compile-time guarantees
+- **Shared Types**: Common types defined in `src/cmd/lib/types.zig` for consistency
+
 ### Implementation Status
 
 #### ✅ **Fully Implemented Features**
@@ -51,14 +59,28 @@ The application uses a type-safe command architecture with Zig unions and enums:
 - **Path Formatting**: DOS-style path display with drive letters and 8.3 filename conversion
 
 #### 📋 **Built-in Commands Available**
+
+**Phase 1 Commands (Core):**
+- **`COPY`** - File copying with overwrite prompts and device handling
+- **`DIR`** - Directory listing with file sizes, counts, and free space display
+- **`TYPE`** - Display file contents with binary character filtering
+- **`CD/CHDIR`** - Directory navigation with path validation
+
+**Phase 2 Commands (Extended File Operations):**
+- **`MD/MKDIR`** - Directory creation with nested path support
+- **`RD/RMDIR`** - Directory removal with safety checks
+- **`REN/RENAME`** - File and directory renaming
+- **`DEL/REMOVE`** - File deletion with wildcard support
+- **`PATH`** - Environment PATH variable management (GET/SET)
+- **`MOVE`** - File/directory moving (placeholder - not yet implemented)
+
+**Shell and System Commands:**
 - **`ECHO`** (with ON/OFF variants) - Text output and echo state control
-- **`CLS`** - Clear screen with ANSI escape sequences
+- **`CLS`** - Clear screen with ANSI escape sequences  
 - **`EXIT`** - Exit the shell
 - **`VER`** - Version information display
 - **`DATE`** - Current system date with proper calendar calculations
 - **`TIME`** - Current system time display
-- **`DIR`** - Directory listing with file sizes and counts
-- **`TYPE`** - Display file contents with binary character filtering
 - **`SORT`** - Alphabetical line sorting with input redirection support
 
 #### 🔧 **External Command Support**
@@ -92,6 +114,36 @@ The application uses a type-safe command architecture with Zig unions and enums:
 - **ANSI Terminal Support**: Cross-platform terminal manipulation
 - **Path Handling**: DOS-style path formatting on all platforms
 
+### Project Structure
+
+```
+src/
+├── cmd/                    # Modular command implementations
+│   ├── lib/
+│   │   └── types.zig      # Shared command types and interfaces
+│   ├── chdir.zig          # CD/CHDIR command
+│   ├── cls.zig            # CLS command  
+│   ├── copy.zig           # COPY command
+│   ├── date.zig           # DATE command
+│   ├── dir.zig            # DIR command
+│   ├── echo.zig           # ECHO command variants
+│   ├── mkdir.zig          # MD/MKDIR command
+│   ├── move.zig           # MOVE command (placeholder)
+│   ├── path.zig           # PATH command (GET/SET)
+│   ├── remove.zig         # DEL/REMOVE command
+│   ├── rename.zig         # REN/RENAME command
+│   ├── rmdir.zig          # RD/RMDIR command
+│   ├── sort.zig           # SORT command
+│   ├── time.zig           # TIME command
+│   └── type.zig           # TYPE command
+├── cmd.zig                # Command type definitions and imports
+├── eval.zig               # Command execution engine
+├── parser.zig             # DOS command line parser
+├── paths.zig              # DOS path formatting utilities  
+├── syntax.zig             # Command syntax structures
+└── main.zig               # Application entry point and REPL
+```
+
 ### Dependencies
 
 **Zero External Dependencies** - The Zig implementation uses only the standard library: