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Tool/function calling
AI can call external tools and APIs to complete tasks.
Explanation
Function calling enables LLMs to not only generate text, but to trigger structured actions - e.g. query a database, send an email or perform a calculation.
How it works
The model receives a list of available functions with descriptions. Based on the user request, it decides which function should be called with which parameters.
Example
An AI assistant that responds to the question "What is the status of my order?" automatically calls the order API and returns the response.
Why it matters
Function calling turns LLMs from pure text generators into actionable systems that can intervene in real business processes.