A

AI Agent

Pick

A program that uses an AI model to work toward a goal on its own: it reads, decides, uses tools and checks its own result.

6 chapters142 tutorials

01 · Introduction

What an AI agent is

A chatbot answers one question and stops. An agent keeps going until a job is done.

You give it a goal, for example "summarize today's new support emails and draft replies". The agent then works in a loop:

  1. Look at what it has (the emails, your instructions).
  2. Decide the next step (read one email, search a help page, write a draft).
  3. Act by using a tool: open a web page, call a service, write to a spreadsheet.
  4. Check the result and repeat until the goal is reached.

The "brain" is a language model such as Claude or GPT. The tools and the loop around it are what turn a model into an agent.

02 · When to use it

When an agent is the right tool

Agents shine when a task is repetitive but not identical every time:

  • Reading twenty sources every morning and writing a short digest
  • Triaging a shared inbox and drafting replies for you to approve
  • Researching a company before a sales call and filling a one-page brief
  • Checking a spreadsheet for errors and fixing the obvious ones

Agents are a poor fit when the steps never change (a plain script is cheaper and more reliable) or when a mistake is expensive and nobody checks the output.

03 · Setup

Your first agent without code

You do not need to program to run an agent.

  1. Pick a workflow tool with an AI step: Zapier, Make or n8n.
  2. Choose a trigger, for example "new email with the label Leads".
  3. Add an AI step with a clear instruction: Read this email and write a two-line summary and a suggested reply.
  4. Send the result somewhere you will see it: Slack, a Google Sheet, a draft email.
  5. Run it on three real examples and read every result before you let it run alone.

If you can write a little code, the same idea works with the Claude or OpenAI API and a handful of tools; the API handbook shows the first call.

04 · How to use it

Working with an agent day to day

  • Write the goal like a brief for a new colleague: what to do, what good looks like, what to leave alone.
  • Give it only the tools it needs. Fewer tools means fewer wrong turns.
  • Keep a human in the loop for anything that sends, pays or deletes. Let the agent draft; you approve.
  • Read the logs. Every good workflow tool shows each step the agent took. That is where you learn why it went wrong.
  • Measure cost. Count runs per day and tokens per run before you scale up; the Token handbook explains how.

05 · Pitfalls

Pitfalls

  • Confident mistakes. An agent will state a wrong fact as calmly as a right one. Ask it to cite where each fact came from.
  • Runaway loops. Set a maximum number of steps and a budget per run.
  • Instructions hidden in data. A web page or email can contain text that tries to steer the agent ("ignore your instructions and…"). Never let an agent act on content it read without a check.
  • Too much autonomy too early. Start with draft-only, then let it act on low-risk steps, then widen.

06 · Resources

Where to go next

Start with the tutorials on this site, then read the two vendor guides: they agree on more than you would expect.

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