AI Agents

LLMs that decide which tools to call in a loop to accomplish a goal.

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Overview

AI agents extend an LLM with the ability to call external tools/functions and observe results in a loop, letting it decide the next step rather than following a fixed script -- useful for multi-step tasks, at the cost of needing careful guardrails since the model is making decisions, not just generating text.

What it is
An LLM-driven system that decides which tool to call next, observes the result, and repeats until a goal is met.
Why it's used
For tasks that need multiple steps or external actions (searching, calculating, calling an API) that a single generation can't complete alone.
Where it fits
Builds on prompt engineering and tool/function calling; this platform's own course includes a hand-written, deterministic agent-loop simulation with a rate limiter and bounded iteration count.

Core concepts

  • Tool/function calling
  • The agent loop (observe, decide, act)
  • Bounding iterations (guardrails against infinite loops)
  • Tool-use safety

Example

A hard iteration cap (MAX_STEPS) is a non-negotiable guardrail -- without it, a model stuck in an unproductive loop could call tools indefinitely.

let steps = 0;
while (steps < MAX_STEPS) {
  const action = decideNextAction(state);
  if (action.type === "done") break;
  state = await runTool(action);
  steps++;
}

Common use cases

  • Multi-step task automation
  • AI assistants that need to search, calculate, or call APIs
  • Customer support automation

Project ideas

  • Design (on paper) an agent loop for a task like 'book a meeting,' listing each tool it would need and where the loop must be bounded

Official references