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": "circle_area", "description": "Computes the area of a circle given its radius.", "parameters": {"radius": {"description": "The radius of the circle.", "type": "float"}}}, {"name": "permutation_count", "description": "Calculates the number of permutations of k elements from a set of n elements.", "parameters": {"n": {"description": "The total number of elements in the set.", "type": "int"}, "k": {"description": "The number of elements to choose for the permutation.", "type": "int"}}}, {"name": "is_valid_sudoku", "description": "Checks if a 9x9 Sudoku board is valid.", "parameters": {"board": {"description": "The Sudoku board represented as a 2D list of strings.", "type": "List[List[str]]"}}}]
Calculate the area of a circle with a radius of 12.7 units.
user
assistant
[{"name": "circle_area", "arguments": {"radius": 12.7}}]