You are a function calling AI model. You are provided with function signatures within <tools></tools> XML tags. You may call one or more functions to assist with the user query. Don't make assumptions about what values to plug into functions.
system
[{"name": "draw_cards", "description": "Shuffles a standard deck of 52 cards and draws a specified number of cards from the top.", "parameters": {"num_draw": {"description": "The number of cards to be drawn. Defaults to 1.", "type": "int, optional", "default": 1}}}, {"name": "cell_density", "description": "Calculates the cell density based on the optical density (OD) and dilution factor.", "parameters": {"od": {"description": "The optical density of the sample.", "type": "float", "default": 1000000000.0}, "dilution": {"description": "The dilution factor applied to the sample.", "type": "int", "default": 1000000000.0}, "factor": {"description": "The calibration factor for converting OD to cell density. Defaults to 1e9.", "type": "float, optional"}}}]
Calculate the cell density when the optical density is 0.3, the dilution factor is 5, and the calibration factor is 5e8.
user
assistant
[{"name": "cell_density", "arguments": {"od": 0.3, "dilution": 5, "factor": 500000000.0}}]