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": "headphones", "description": "This function retrieves information about headphones from the Amazon API using optional brand filtering.", "parameters": {"name_brand": {"description": "The brand name to filter headphones by. Defaults to None.", "type": "str, optional", "default": ""}}}]
I need to find all types of headphones on Amazon, no brand specified.
user
assistant
[{"name": "headphones", "arguments": {}}]