Address PR feedback: Add logging, input validation, and error handling

Co-Authored-By: Joe Moura <joao@crewai.com>

examples/custom_flow_script.py

@@ -4,10 +4,15 @@ Example script showing how to run a CrewAI flow from a custom script.
 This example demonstrates how to avoid the ModuleNotFoundError when 
 starting flows from custom scripts outside of the CLI command context.
 """
+import logging
 import os
 
 from crewai.utilities.path_utils import add_project_to_path
 
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+logger.info("Adding project directory to Python path")
 add_project_to_path()
 
 from my_flow.main import MyFlow  # noqa: E402

src/crewai/cli/kickoff_flow.py

@@ -9,7 +9,11 @@ def kickoff_flow() -> None:
     """
     Kickoff the flow by running a command in the UV environment.
     """
-    add_project_to_path()
+    try:
+        add_project_to_path()
+    except ValueError as e:
+        click.echo(f"Error setting up project path: {e}", err=True)
+        return
     
     command = ["uv", "run", "kickoff"]
 

src/crewai/utilities/path_utils.py

@@ -1,9 +1,13 @@
+import logging
 import os
 import sys
 from pathlib import Path
 from typing import Optional
 
 
+logger = logging.getLogger(__name__)
+
+
 def add_project_to_path(project_dir: Optional[str] = None) -> None:
     """
     Add the project directory to the Python path to resolve module imports.
@@ -15,6 +19,9 @@ def add_project_to_path(project_dir: Optional[str] = None) -> None:
         project_dir: Optional path to the project directory. If not provided,
                      the current working directory is used.
     
+    Raises:
+        ValueError: If the provided directory does not exist.
+    
     Example:
         ```python
         from crewai.utilities.path_utils import add_project_to_path
@@ -29,15 +36,26 @@ def add_project_to_path(project_dir: Optional[str] = None) -> None:
     """
     if project_dir is None:
         project_dir = os.getcwd()
+        logger.debug(f"Using current working directory: {project_dir}")
+    else:
+        logger.debug(f"Using provided directory: {project_dir}")
     
     project_path = Path(project_dir).resolve()
     
+    if not project_path.exists():
+        raise ValueError(f"Invalid directory: {project_dir} does not exist")
+    
     if (project_path / "src").exists() and (project_path / "src").is_dir():
+        logger.debug(f"Found 'src' directory in {project_path}")
         if str(project_path) not in sys.path:
             sys.path.insert(0, str(project_path))
+            logger.debug(f"Added {project_path} to sys.path")
         
         if str(project_path / "src") not in sys.path:
             sys.path.insert(0, str(project_path / "src"))
+            logger.debug(f"Added {project_path / 'src'} to sys.path")
     else:
+        logger.debug(f"No 'src' directory found in {project_path}")
         if str(project_path) not in sys.path:
             sys.path.insert(0, str(project_path))
+            logger.debug(f"Added {project_path} to sys.path")