diff --git a/test/test_cli.py b/test/test_cli.py
new file mode 100644
index 0000000..f6a98da
--- /dev/null
+++ b/test/test_cli.py
@@ -0,0 +1,80 @@
+import pytest
+from typer.testing import CliRunner
+from unittest.mock import patch, MagicMock
+from pathlib import Path
+from photools3.cli import app
+
+runner = CliRunner()
+
+@pytest.fixture
+def mock_photo_logic(tmp_path):
+    """Fixture to mock the core logic of keywords command."""
+    with patch("photools3.cli.LlmSessionCaptionsAndKeywords") as mocked_session, \
+         patch("photools3.cli.Photo") as mocked_photo:
+        
+        # Configure session mock
+        session_instance = mocked_session.return_value
+        session_instance.call.return_value = {
+            "caption": "A beautiful test image",
+            "args": ["test", "mock", "image"] # Wait, the code uses 'tags'
+        }
+        # Let me re-check the code in cli.py
+        # result.get("tags", [])
+        session_instance.call.return_value = {
+            "caption": "A beautiful test image",
+            "tags": ["test", "mock", "image"]
+        }
+        
+        # Configure photo mock
+        photo_instance = mocked_photo.return_value
+        photo_instance.path = tmp_path / "test_image.jpg"
+        
+        yield {
+            "session": session_instance,
+            "photo_class": mocked_photo,
+            "photo_instance": photo_instance
+        }
+
+@pytest.fixture
+def dummy_file(tmp_path):
+    """Fixture to create a dummy file for CLI testing."""
+    dummy_path = tmp_path / "test_image.jpg"
+    dummy_path.write_text("dummy content")
+    return dummy_path
+
+def test_keywords_command_success(mock_photo_logic, dummy_file):
+    """Test the 'keywords' command with a valid file path."""
+    # Ensure the mock photo instance points to our dummy file
+    mock_photo_logic["photo_class"].return_value.path = dummy_file
+    
+    result = runner.invoke(app, ["keywords", str(dummy_file)])
+    
+    assert result.exit_code == 0
+    assert "Processing: " in result.stdout
+    assert "Caption: A beautiful test image" in result.stdout
+    assert "Tags: test, mock, image" in result.stdout
+
+def test_keywords_command_file_not_found():
+    """Test the 'keywords' command with a non-existent file path."""
+    non_existent_file = Path("non_existent_file.jpg")
+    result = runner.invoke(app, ["keywords", str(non_existent_file)])
+    
+    assert result.exit_code == 1
+    assert f"Error: File '{non_existent_file}' does not exist." in result.stderr
+
+def test_keywords_command_error_during_processing(mock_photo_logic, dummy_file):
+    """Test the 'keywords' command when an exception occurs during processing."""
+    # Configure the session mock to raise an exception
+    mock_photo_logic["session"].call.side_effect = Exception("LLM error")
+    
+    result = runner.invoke(app, ["keywords", str(dummy_file)])
+    
+    assert result.exit_code == 1
+    assert "Error processing image: LLM error" in result.stderr
+
+def test_version_command():
+    """Test the --version option."""
+    result = runner.invoke(app, ["--version"])
+    
+    assert result.exit_code == 0
+    assert "photools3 version 0.1.0" in result.stdout