What is a tool function in the context of Claude implementation?	A Python function that is executed automatically when Claude determines it needs to retrieve extra information.
What is the first step when adding a new tool to the implementation?	Writing out a tool function.
List three best practices for writing tool functions.	Use well-named and descriptive arguments; validate inputs and raise errors; and ensure error messages are meaningful.
Why is it important to include meaningful error messages when a tool function fails?	So Claude can see the error and attempt to correct its tool call in a subsequent attempt.
What is the purpose of the `date format` argument in the `get current date time` function?	To specify the exact string format in which the current date and time should be returned.
What specific validation check was suggested for the `date format` argument?	Checking if the argument is an empty string and raising a `ValueError` if it is.
How is the current date and time retrieved and formatted within the `get current date time` function?	By using `datetime.now().strftime(date_format)`.