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Technology

Tool Use / Function Calling

The ability of AI models to invoke external tools, APIs, or functions during a conversation. Enables AI to perform real actions — searching the web, querying databases, sending emails, or running calculations — not just generate text.

Why it matters

Tool use is what turns a chatbot into something that can actually do things, like check live data, send an email, or run a calculation, instead of only talking about them. It's the foundation of AI agents and modern assistants that book, search, and update on your behalf. Understanding it helps you see why some AI tools stay current and take action while plain chatbots are stuck with old training knowledge.

In practice

You ask an assistant, "What's the weather in Chicago and add a reminder to pack an umbrella?" Instead of guessing, it calls a weather API for the real forecast, then calls your calendar tool to create the reminder. A tip: when a tool-enabled assistant can connect to your apps, be specific about what you want it to do, since it will take those real actions literally.

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