AI Agent
A software system powered by an AI model that autonomously perceives its environment, makes decisions, and takes actions to achieve a specified goal.
What Is AI Agent?
An AI agent is a system that combines an LLM's reasoning abilities with the ability to take actions in the world — searching the web, writing and running code, sending emails, or interacting with APIs. The defining characteristic is agency: the model does not just respond to prompts, it plans and executes a sequence of steps to accomplish a goal, adjusting based on what it observes.
The agent loop consists of four phases: Observe (receive the current state of the environment), Think (reason about what to do next), Act (call a tool or produce output), and Reflect (evaluate the result and decide whether the goal is achieved). This loop repeats until the task is complete or the agent gives up.
Why It Matters
AI agents are the primary vehicle through which LLMs become economically transformative. Tasks that required hours of human effort — research, data processing, code writing — can be delegated to agents running 24/7. The challenge is reliability: agents can take consequential actions autonomously, so safety, monitoring, and human-in-the-loop design are critical.
Real-World Examples
Coding Agent
Claude Code is an AI agent. Given a task description, it reads files, writes code, runs tests, and creates commits — all in an autonomous loop.