Reasoning is what separates an agentic system from a simple lookup tool. When an agent receives a goal, it evaluates the situation, forms a plan, executes steps, checks results, and revises its approach when things do not go as expected. This is often implemented using Chain-of-Thought prompting, ReAct loops, or tool-augmented planning.
An IT support agent receiving a VPN failure ticket does not just return a generic FAQ response. It checks whether the user is on the approved device list, looks for prior occurrences of the same error, checks for known outages, and responds based on what it finds. That kind of situational awareness only comes from genuine reasoning.
