What is Function calling (tool use)?
Function calling, also called tool use, is a capability that lets a language model request an action from external software, such as looking up an order or creating a ticket, by returning structured inputs for a predefined function. The application runs the function and passes the result back to the model.
Why it matters for your business
Function calling is what connects an AI assistant to your real systems and data, so it can give current, accurate answers and complete tasks instead of only generating text.
A customer asks a chatbot where their package is. The model calls an order lookup function with the order number, receives the tracking status and replies with it.