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Glossary

AI agent

An AI agent is a system given a goal rather than a question, which decides its own steps, uses tools such as search or a calendar to carry them out, then checks the results and adjusts until it finishes.

In plain terms

The difference is between asking someone a question and giving them a job. A question gets one answer back. A job means they work out what to do first, go and do it, notice when something has not worked, and try a different way. Everything that makes the second more useful to you also makes it harder for you to supervise.

01

Why it matters

This is where most of the current effort and most of the current disappointment are concentrated. The promise is genuine: work that used to need a person shepherding it step by step can run unattended, which is a different order of saving from drafting help. The catch is that errors compound. A chatbot that gets one answer wrong wastes a minute, whereas a system taking twenty steps on your behalf can be wrong at step three and spend the remaining seventeen building on it. Judging these tools well means asking what happens when a step fails, not what happens when every step succeeds.

02

How it works

The loop is short and it is the whole idea. The system is given a goal, decides what to do next, does it, looks at the result, and decides again with that result now in front of it. Nothing about this is new as a pattern; what changed is that a model good enough at language turned out to be good enough to pick the next step from a description of the situation.

The steps are taken through tools. A tool is anything the system can call and get a result from: a web search, a calendar, a spreadsheet, a database query, another piece of software's interface. The set of tools available is what decides the boundary of what an agent can actually do, which is why two products built on the same model can feel so different when you try them.

Planning may be explicit or implicit. Some systems write a plan first and work through it, which is easier to inspect and slower to adapt. Others decide only the immediate next step each time, which is more flexible and harder to follow after the fact. Neither is a guarantee of good judgement, and a written plan can look sound while resting on a wrong assumption made in its first line.

Stopping is a design problem in its own right. Left alone the loop has no natural end, so systems are given limits: a maximum number of steps, a budget, a time cap, or a check that asks whether the goal is met. Runaway cost is a real failure mode, and so is stopping too early with a job half done and reported as finished.

Everything the agent has learned along the way has to fit in the same fixed budget as any other request. Twenty steps of results accumulate, and once the total exceeds what the model can hold, early findings drop out. This is why long agent runs tend to lose the thread rather than gently degrade, and why summarising as it goes is a common part of the design.

Approval gates are where most of the safety comes from. A system that reads and drafts can be allowed to run freely, because the worst case is a wasted run. A system that sends, pays, deletes or commits needs a person between the decision and the action for anything irreversible. Deciding which of your actions need that gate is the main design judgement in agent work, and it is yours to make rather than the vendor's.

Agentic AI and autonomous agent are the same idea under other names. Agentic is the adjective, describing software with any of this loop-and-tools character, and it is applied loosely enough that you will meet it on products making a single tool call. Autonomous emphasises running without supervision, which is a spectrum rather than a state: almost everything sold to you as autonomous still has limits, approval points and a human who set the goal.

The loop, which is the whole idea

The loop, which is the whole ideaA goal goes in, and from there the same four steps repeat until something stops them. The system decides what to do next, does it through a tool, reads what came back, and decides again with that result in front of it. Nothing about the pattern is new; what changed is that a model good enough at language turned out to be good enough to pick the next step from a description of the situation. Two things follow from the loop having no natural end. It needs a stopping condition, whether a step limit, a budget or a check that the goal is met. And every pass through it is another chance to be wrong, which is what the second drawing on this page is about.givensearch,calendar,databasea resultdecide again,now knowing moreA goalDecide what to do nextAct, through a toolRead what came back
A goal goes in, and from there the same four steps repeat until something stops them. The system decides what to do next, does it through a tool, reads what came back, and decides again with that result in front of it. Nothing about the pattern is new; what changed is that a model good enough at language turned out to be good enough to pick the next step from a description of the situation. Two things follow from the loop having no natural end. It needs a stopping condition, whether a step limit, a budget or a check that the goal is met. And every pass through it is another chance to be wrong, which is what the second drawing on this page is about.

Why a run of twenty steps disappoints when each step is good

Why a run of twenty steps disappoints when each step is goodTake a step that succeeds nineteen times out of twenty, which would be a good step. Chain five of them and the run finishes clean about seventy-seven times in a hundred. Chain twenty and it is about thirty-six. Chain forty and it is about thirteen. Nothing has got worse; reliability simply multiplies rather than averaging, so a per-step figure that sounds strong becomes a per-run figure that does not. This is the arithmetic behind agents impressing in a three-step demonstration and frustrating on twenty steps of real work, and it is why checkpoints and approval gates do more for a long run than making each individual step slightly better.1 step95 in 100finishclean5 steps77 in 10010 steps60 in 10020 steps36 in 10040 steps13 in 100
Take a step that succeeds nineteen times out of twenty, which would be a good step. Chain five of them and the run finishes clean about seventy-seven times in a hundred. Chain twenty and it is about thirty-six. Chain forty and it is about thirteen. Nothing has got worse; reliability simply multiplies rather than averaging, so a per-step figure that sounds strong becomes a per-run figure that does not. This is the arithmetic behind agents impressing in a three-step demonstration and frustrating on twenty steps of real work, and it is why checkpoints and approval gates do more for a long run than making each individual step slightly better.
03

Seen in the wild

  • Set up a multi-step flow on an automation platform where each step's output decides the next, which is the loop with the decisions made in advance by you rather than at run time.

    Zapier
  • Give a coding assistant a task in a repository and watch it read files, make a change, run the tests and react to the failures, which is the loop with a real feedback signal.

    Claude Code
  • Build an assistant that handles a recurring task end to end on a self-hostable platform, where the tools it may call are ones you have connected deliberately.

    n8n
  • Use a research assistant that runs several searches, reads what it finds and searches again based on the gaps, rather than answering from one pass.

    Perplexity
04

Common misconceptions

People assume

An agent is a smarter kind of chatbot.

In fact

It is the same kind of model wired into a loop with tools. The intelligence per step is roughly what you get from the chat window; what is added is persistence, the ability to act, and the ability to react to results. That is a change in capability rather than in cleverness.

People assume

More autonomy is better.

In fact

More autonomy is better only where a wrong action is cheap to undo. Reading, researching and drafting suit it well. Sending, paying, deleting and publishing usually do not, because the cost of the rare bad decision outweighs the saving on the routine ones. The useful question is which actions need a person, not how few.

People assume

If each step is usually right, the whole run will be.

In fact

Reliability multiplies rather than averaging. A step that succeeds nineteen times in twenty gives a twenty-step run barely a one-in-three chance of finishing clean. This is why agents feel impressive in demonstrations of three steps and frustrating on real work of twenty, and why checkpoints matter more than per-step quality.

05

Telling them apart

AI agent vs Automation

AI agent

Decides the steps at run time from a goal. Handles cases nobody wrote a rule for, and can surprise you in both directions.

Automation

Follows steps decided in advance. Does exactly the same thing every time, which is a limitation on messy work and a virtue everywhere else.

If someone drew the flowchart, it is automation. If the flowchart is decided while it runs, it is an agent. Most useful systems are mainly the first with the second at the one genuinely variable step.

AI agent vs Workflow orchestration

AI agent

The decision-maker: what to do next, given where things have got to.

Workflow orchestration

The machinery that runs multi-step work reliably: ordering, retries, error handling, state, and picking up after a failure.

Anything running agents in production needs both. The agent decides; the orchestration is what stops step fourteen failing quietly at three in the morning.

06

Questions

What is the difference between an AI agent and agentic AI?
Mostly grammar. Agent names the system; agentic is the adjective for software with that loop-and-tools character. The adjective is applied loosely in marketing, including to products that make a single tool call, so it is worth asking what the system actually decides for itself rather than reading the label.
Are AI agents reliable enough for real work?
For bounded tasks with cheap failure and a person reviewing the result, yes, and they are in production use. For long unattended runs that take consequential actions, the compounding-error problem is real and unsolved. The practical pattern is narrow scope, explicit stopping conditions, and approval gates on anything irreversible.
What tools can an agent use?
Whatever it has been connected to: search, calendars, email, spreadsheets, databases, other software's interfaces, and increasingly connectors built to a shared standard. The available set defines the boundary of what it can do, so comparing agent products is largely comparing what each one can reach.
Will an agent spend money without asking?
Only if it has been given a tool that can, and permission to use it unsupervised. Sensible deployments put an approval step in front of anything irreversible, spending included. Where a product offers unattended purchasing, treat the spending limit and the approval settings as the first thing to configure rather than a detail.
Do I need an agent, or would automation do?
If you can write down the steps, automation is cheaper, faster and more predictable, and it does not need a model at all. Agents earn their cost where the steps genuinely vary with what is found, such as research, triage or investigation. Many good systems are automation with one agentic step inside them.
07

Key takeaways

  • An agent is given a goal rather than a question, and decides its own steps towards it.
  • It acts through tools, so the connected set defines the boundary of what it can do.
  • Errors compound across steps, which is why demonstrations impress and long runs disappoint.
  • Stopping conditions and approval gates on irreversible actions are the main safety design.
  • Agentic AI and autonomous agent are the same idea, applied loosely as marketing adjectives.
09

Tools that use this

  • Zapier

    Multi-step flows where the sequence is fixed, which is the useful contrast case.

  • Claude Code

    Reads, edits and runs tests, so the loop has a real feedback signal to react to.

  • n8n

    Self-hostable, so the tools an agent may call are ones you connected deliberately.

  • Lindy

    Assistants built around recurring tasks rather than one-off questions.

Last checked July 2026

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