Glossary · Artificial intelligence

What is an AI agent

An AI agent is a system that uses a language model to achieve a goal: it interprets the request, decides the next step and acts in other systems — looking up a record, logging it in the CRM, booking a time slot — within defined limits. A chatbot follows a fixed script; a model only generates text; an agent acts.

The term has become a label for almost anything with AI in it. The useful definition is narrower: an agent has a goal, tools it can use and rules about when to stop. Without all three, what you have is a chatbot that writes better.

AI agent, chatbot and language model

The three are often treated as synonyms, but they aren't. The language model is the engine; the chatbot is a script, with or without that engine; the agent is the engine plus a goal, tools and rules.

Difference between a language model, a flow-based chatbot and an AI agent
CriterionLanguage modelFlow-based chatbotAI agent
What it isSoftware that generates text from a promptA tree of menus and replies designed by someoneA language model with a goal, tools and rules
How it decides what to doIt doesn't decide: it responds to the prompt it receivedFollows the path laid out for each optionPicks the next action based on the conversation, within what's allowed
Acts in other systemsNot on its ownOnly through the flow's fixed integrationsYes: reads from and writes to the CRM, calendar, catalog
Where it failsMakes up an answer when it doesn't knowGets stuck when the conversation goes off scriptCan take the wrong action if the limits aren't written down
Sales exampleDrafting a proposal from notesTriage menu: press 1 for a quoteResponding to the lead, qualifying them and booking the meeting in the CRM

How an agent works under the hood

Every agent, from any vendor, is built from the same parts. When one of them is missing, that's usually where the project breaks:

  • Goal: what the agent needs to achieve — qualify a lead, confirm an order, answer a question
  • Instructions and rules: what it can and can't do, written by the company
  • Tools: the systems it reads from and writes to, such as the CRM, calendar and product catalog
  • Context: the contact's history and the knowledge base it can use to answer
  • Exit point: the rule that hands the conversation to a person when the case is out of scope

Examples in sales and customer service

In sales, an agent makes sense for high-volume tasks with clear rules — exactly the ones that tend to get pushed aside when the team is busy:

  • Responding to the lead who writes at night or on the weekend, instead of leaving them waiting until the next morning
  • Asking the qualification questions the team already uses and saving the answers to the opportunity
  • Offering open slots on the assigned rep's calendar and confirming the meeting
  • Following up with people who stopped responding, taking into account what was already said in the conversation
  • Separating quote requests, post-sale questions and complaints, and routing each one to whoever handles it

Limits: what an agent shouldn't do

An agent won't stop on its own when it faces a situation it shouldn't handle. That's why the limits are written before it goes live, not after the first problem:

  • Promising a price, timeline or terms outside the written sales policy
  • Answering questions about things that aren't in its knowledge base — the language model can make up an answer with complete confidence
  • Handling complaints, collections or sensitive situations without a person
  • Taking actions that are hard to undo, like canceling an order, without confirmation
  • Collecting more personal data than necessary; customers should know they're talking to an automated assistant, and data handling follows the LGPD (Brazil's data protection law)

How to implement it carefully

The approach that works starts small: one task, one written criterion and one rule for handing off to a human. The agent is connected to the system where the data already lives — in sales, the CRM and the channel the customer uses, which in Brazil is almost always WhatsApp — and it's tuned in the first few weeks by reading real conversations, not by the impression from the demo.

The step-by-step applied to sales operations, with what an agent does and where it shouldn't act, is on the AI agents for business page. The detailed comparison with flow-based chatbots, including when a chatbot is still the better choice, is in the comparison between the two.

Frequently asked questions

Is an AI agent the same thing as an assistant like ChatGPT?

No. A chat assistant responds to what a person asks. An agent uses a language model as its engine, but it's given a goal, tools to act in other systems and rules about what it can do — and it works within that scope without someone dictating every step.

What's the difference between an AI agent and a chatbot?

A flow-based chatbot follows a script of menus and gets stuck when the conversation goes off track. An agent interprets the message, checks the context and picks the next action within rules. That's why it can handle open-ended conversation — and why it requires better-written limits.

Does an AI agent replace sales reps?

No. It takes over the repetitive work — first response, qualification, scheduling, follow-up — and hands the conversation to a person when negotiation, complex objections or decisions that require judgment come in.

Can an AI agent make mistakes?

Yes. The language model can make up an answer, and the agent can act on it. That's why it works with a closed scope, a defined knowledge base, a rule for handing off to a human and frequent review of its conversations.

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