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": "cagr", "description": "Calculates the Compound Annual Growth Rate (CAGR) of an investment.", "parameters": {"start_value": {"description": "The initial value of the investment.", "type": "float"}, "end_value": {"description": "The final value of the investment.", "type": "float"}, "years": {"description": "The number of years between the initial and final values.", "type": "int"}}}]
Determine the CAGR if an investment of $20,000 increased to $25,000 over 4 years.
user
assistant
[{"name": "cagr", "arguments": {"start_value": 20000, "end_value": 25000, "years": 4}}]