Tool use
Also called function calling, tool calling.
Tool use is an AI system's ability to request an action from connected software, such as searching files or running code.
Example
A bot needs today's date from a calendar. It requests the calendar tool instead of guessing. The app runs the request only if that connectorA connector is a ready-made connection that lets an application use another service's data or actions. is allowed.
Why it matters
The model proposes a tool call. The application around it decides whether the call may run. That decision is a permission, not part of the model's grammar.
Common confusion
Tool use is a request to software. It is not proof the action already happened, and it is not the same thing as a pluginA plugin is an optional piece of software that adds a feature to a larger application. you installed.
Sources
Updated September 30, 2026.