What does “Tool Use” mean?

A model capability to generate structured calls that trigger external tools or APIs.

Model output constrained to a defined schema such as JSON, tool arguments, or typed fields.

An open protocol that lets AI applications connect to external tools, data sources, and context providers in a standard way.

A prompting pattern that interleaves reasoning steps with tool-use actions to solve tasks more reliably.

A chunk of text processed by language models, such as a word piece or symbol.

A software system that can observe, reason, and take actions to achieve a goal, often using tools and memory.