Tool Use (Function Calling)
The ability of a model to call external functions, like search, a calendar, or your database, and use the results.
Tools are what turn talk into action. Without them, an agent can only describe; with them, it can do.
Frequently asked questions
What does tool use mean for an AI?
Tool use, also called function calling, is a model's ability to call outside functions like search, a calendar, or a database and then use the results. It is what turns an AI that only talks into one that can actually do things.
How does an AI agent take real actions instead of just describing them?
Through tool use: instead of only writing about booking an appointment, the agent can call a calendar tool and actually book it. Without tools an agent can only describe; with them it can act on real systems.
Is function calling the same as tool use?
Yes, they are two names for the same idea: the model reaching out to an external function and using what comes back. You will hear tool use in plain talk and function calling in more technical settings.
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