Tool use is the capability that turns a language model from a text generator into an agent. When a model can use tools — search engines, calculators, databases, APIs, code interpreters — it can take real actions rather than only describing what should be done.
The range and reliability of tool use is a primary differentiator between basic and advanced AI agents. An agent with access to a handful of pre-defined tools can handle the cases those tools cover. An agent with broad, reliable tool use capability can handle nearly anything within its domain — adapting its approach based on what tools are available and what the situation requires.
