Function calling
Level 3
The mechanism that lets a model request a specific piece of software with specific inputs.
Term 3 of 7 in AI agents
In plain language
Rather than guessing, the model outputs a structured request: this function, these values. The surrounding program runs it and hands the result back.
Think of it like this
Filling in a form to place an order, instead of shouting your request across the room.
Why it matters
Function calling is the plumbing behind almost every reliable agent. It turns loose language into something software can execute.