What are AI Agents?

What are AI Agents?

An AI agent is an autonomous system that perceives its environment, reasons using an LLM, takes actions through tools, and iterates until a goal is achieved — going far beyond simple question-answering.

• Perceive: read files, call APIs, browse web
• Reason: LLM decides what to do next
• Act: call tools, write code, send messages
• Iterate: loop until goal is complete

# Agent vs LLM call
# LLM call:  prompt -> response (one shot)
# Agent:     goal -> [think -> act -> observe] * N -> result

# Simple ReAct loop
while not done:
    thought = llm.think(goal, history, observations)
    action  = llm.decide_action(thought)
    result  = execute_tool(action)
    observations.append(result)
    done = llm.check_if_complete(result)