Acting / Tool Invocation

Acting, also called tool invocation, is the step where the AI chooses a tool and runs it to get real-world data or to change something. The agent looks at its current goal and the plan it just made. It then picks the best tool, such as a web search, a database query, or a calculator. The agent fills in the needed inputs and sends the call. The external system does the heavy work and returns a result. Acting ends when the agent stores that result so it can think about the next move.