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": "steam", "description": "Checks the availability of a given username on Steam using the Toolbench RapidAPI service.", "parameters": {"username": {"description": "The username to check for availability on Steam.", "type": "str", "default": "username"}}}]
Is the username 'EpicGamer888' already taken on Steam? Also, verify the availability of 'NovaStar999'.
user
assistant
[{"name": "steam", "arguments": {"username": "EpicGamer888"}}, {"name": "steam", "arguments": {"username": "NovaStar999"}}]