AI
May 19, 2025

Understanding the Different Types of AI Agents: A Deep Dive with Examples

Contributors
Dhanashree B
Product Marketing Manager
Updated on
May 19, 2025

AI agents are no longer a futuristic concept. From voice assistants to customer service chatbots, these agents now play an active role in how we live, work, and interact. But what exactly are AI agents, how do they operate, and what makes one type different from another?

In this article, we'll break down what AI agents are, the different types of AI agents with examples, and how they relate to concepts like types of agent authority and the 3 types of agency relationships in decision-making systems.

What Is an AI Agent?

An AI agent is a system capable of perceiving its environment through sensors and acting upon that environment using actuators to achieve specific goals. In simple terms, it’s a program or system that can understand a problem and take actions accordingly, sometimes even improving with time.

A type of AI agent

Types of AI Agents (With Examples)

In this blog, we will focus on different types of AI agents. There are four basic types of AI agents in order of increasing generality:

  • Simple Reflex Agent
  • Model-based reflex agent
  • Goal-based agents
  • Utility-based agent
  • Learning agent

Let’s look at all of them one by one.

Simple Reflex Agent

A Simple Reflex Agent is a type of AI agent that only uses current data and it ignores any past data. It uses a set of condition-action rules coded into the system to make its decision or take any action.

For example, imagine a vending machine as a simple reflex agent.

  • You input money (condition) and
  • select a snack (action), and
  • the machine dispenses your choice based solely on that immediate input, without considering past or future transactions.

Simple reflex agents are straightforward and are suitable for simple situations where a condition leads to an action, just like our vending machine example. If we were to look at simple reflex agents and their interaction with their environment, sensors, it would look something like the image below.

Simplex Agent interaction with environment and sensors.

 

Pros and Cons of using Simple reflex agents: 

Pros:

  • Easy to design 
  • Easy to implement for specific tasks.
  • Responses quickly to any stimuli without complex processing. 

Cons:

  • Limited Flexibility: Unable to handle unexpected or unprogrammed situations.
  • Lack of Context: Does not consider past interactions, leading to potentially suboptimal decisions.

Model-based Reflex Agent

Model-based reflex agents use the current state of the world & the internal model of that world, to decide on the best action. It partially observes the external environment by maintaining an internal environment. 

Model based reflex agent

Let’s understand it using an example of a thermostat which regulates the house temperature. It compares the inner house temperature (environment) with the temperature set by the user (internal environment) to identify whether it should turn heating/cooling on or off (action). 

Model-based reflex agents are useful in environments where complete information isn’t available, and some form of history or state needs to be considered. They're effective in applications like autocorrect where it adjusts based on the user's typing habits.

Pros and Cons of using model based reflex agents

Pros:

  • You can adjust actions based on changes in the environment.
  • It uses an internal model to make informed decisions, even with incomplete information.

Cons:

  • Complex to design and implement than simple reflex agents.
  • The internal model may need regular updates.

Goal-based Agents

Goal-based agents act to achieve specific goals, using the model of the world to consider the future consequences of their actions. They choose actions that lead them closer to their predefined goals. 

Goal based agents

Imagine a goal-based agent as a GPS navigation system. Given a destination (goal), it evaluates various routes (actions) using its world model (maps and traffic conditions) to recommend the fastest or shortest path, adjusting as conditions change.

Goal-based agents are ideal for complex planning and decision-making tasks where achieving a specific outcome is the priority. They're used in strategic game playing, automated planning in logistics, and resource allocation in project management, where considering future steps towards a goal is essential.

Pros and Cons of using goal-based agents

Pros:

  • It is capable of adapting to achieve goals under changing conditions.
  • It considers future consequences of actions, leading to more strategic decision-making.

Cons:

  • It requires more processing power for planning and evaluating potential actions.
  • It is focused on goal achievement, which may not always align with the best overall outcome.

Utility-based Agent

Utility-based agents aim not just to achieve goals but to maximize a measure of satisfaction or happiness, known as utility. They evaluate the potential utility of different states and choose actions that maximize this utility.

Utility based AI agent

Think of a utility-based agent as a savvy investor. Given various investment options (states), the investor evaluates each based on potential returns and risks (utility), aiming to maximize overall portfolio satisfaction rather than just achieving a set financial goal.

Utility-based agents are useful in scenarios requiring optimization among various competing criteria or preferences. They excel in financial analysis, complex resource management, and personalized recommendation systems where the best outcome depends on maximizing certain metrics.

Pros and Cons of using utility based agents

Pros:

  • It focuses on maximizing satisfaction, leading to potentially better overall outcomes.
  • It considers a broader range of factors, leading to more nuanced decision-making.

Cons:

  • Determining and quantifying utility can be challenging.
  • Evaluating and comparing utilities for different actions can be resource-intensive.

Learning Agent

Learning agents improve their performance and adapt to new circumstances over time. They can modify their behavior based on past experiences and feedback, learning from the environment to make better decisions.

Learning AI agent

Consider a learning agent as a student mastering a subject. With each lesson, homework, and test (experiences and feedback), the student (agent) learns and adjusts study habits (behavior) to improve grades (performance) over time.

Learning agents are pivotal in dynamic environments where conditions constantly change, or in tasks where human expertise and intuition are difficult to codify. They're employed in adaptive systems such as personalized learning platforms, market trend analysis tools, and evolving security systems that adapt to new threats.

Pros and Cons of using learning agents

Pros:

  • It continuously improves and adapts to new information.
  • It learns from experiences, reducing the need for extensive programming for all possible scenarios.

Cons:

  • It may perform sub optimally during the initial learning phase.
  • The learning processes can lead to unexpected behaviors, requiring safeguards and monitoring.

You can read more about AI agents in our detailed blog.

Types of Agent Authority

In both legal frameworks and intelligent system design, understanding types of agent authority is essential for defining how decisions are made and who is accountable for them.

1. Express Authority

This is the clearest and most direct form of authority.
It occurs when a principal explicitly tells the agent what they are authorized to do—either in writing or verbally.

  • Legal Example: A real estate agent authorized in writing to sell a property at a specific price.
  • AI Parallel: A sales AI assistant given strict rules to generate quotes within a defined price range. The AI operates only within this clearly defined scope.

2. Implied Authority

Implied authority is not explicitly stated but is assumed as necessary to carry out express authority. It arises from the nature of the agent's duties or customary business practices.

  • Legal Example: A store manager has implied authority to hire temporary staff or order inventory even if not specifically instructed each time.
  • AI Parallel: An AI system trained to answer customer queries might also generate follow-up emails or auto-log tickets to fulfill its main goal of improving customer service.

3. Apparent Authority (or Ostensible Authority)

Apparent authority exists when a third party reasonably believes the agent has authority, based on the principal’s behavior or representations—even if that authority was never formally granted.

  • Legal Example: A former employee continues negotiating on behalf of a company, and the company does not explicitly inform third parties of their termination.
  • AI Parallel: A chatbot with branding and integration may be assumed to speak on behalf of the company, even if its scope is limited. Any misleading response could legally or reputationally bind the organization.

3 Types of Agency Relationships

Understanding how agents interact with principals and third parties is crucial in both legal practice and AI agent system design.

1. Principal-Agent Relationship

This is the core relationship where the agent acts on behalf of the principal. The principal is liable for the agent’s actions within the defined scope of authority.

  • Legal Example: A lawyer (agent) negotiating a settlement for a client (principal).
  • AI Parallel: An AI agent that represents a sales team in responding to RFQs and making pricing decisions, within rules set by the company.

2. Agent-Third Party Relationship

This describes the direct interaction between the agent and an external party. The agent’s statements and actions can bind the principal if they’re within their authority.

  • Legal Example: A purchasing agent ordering supplies from a vendor.
  • AI Parallel: A virtual agent communicating with customers, suppliers, or users on behalf of a company through APIs or live chat interfaces.

3. Principal-Third Party Relationship

This is the end-result connection formed as a consequence of the agent’s actions. Even if the principal doesn’t directly engage with the third party, they are still bound by the agreements made by their authorized agent.

  • Legal Example: A business is held to a contract signed by their agent.
  • AI Parallel: A company is held accountable for commitments made by its AI assistant in an automated customer service exchange, especially if no disclaimers or safeguards are in place.

Connection to Real-World Agency Models

In law and business, agency refers to the relationship between a principal and their agent. This concept parallels how AI agents operate under certain types of decision authority.

Types of Agent Authority

Understanding AI agents through this lens:

  • Actual Authority: The AI is programmed with explicit instructions (e.g., a chatbot that follows company policy).
  • Apparent Authority: The AI appears to have authority based on user perception (e.g., AI sales assistants that guide customer decisions).
  • Implied Authority: The AI takes actions reasonably necessary to carry out its explicit tasks (e.g., automated workflow bots).

3 Types of Agency Relationships

Similar to human agents, AI agents can align with different relationship types:

  • Agent to Principal (Direct Authority): AI acts on behalf of the user, such as virtual assistants making calendar bookings.
  • Agent to Third Party (Representing a Business): AI handles customer interactions as a representative of a company.
  • Dual Agency (Shared Interests): AI systems balancing between buyer and seller needs in a marketplace platform.

These legal analogies help us frame AI authority and its implications in automated systems.

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Conclusion

As AI agents become more autonomous and embedded in high-stakes environments like sales, customer service, finance, and legal support, understanding the types of agent authority and agency relationships becomes non-negotiable.

Whether you’re designing a human-agent contract or building a generative AI copilot, clear boundaries must be drawn regarding:

  • What the agent can do (express and implied authority)
  • What third parties might reasonably assume (apparent authority)
  • Who is responsible when decisions are made (agency relationships)

This clarity protects your business, builds trust, and ensures your AI agents—or human ones—operate effectively and ethically.

Read more:

Knowledge FAQ Accordion

FAQs: Everything You Need to Know

Simple Reflex Agent
Model-Based Reflex Agent
Goal-Based Agent
Utility-Based Agent
Learning Agent

Reactive Machines
Limited Memory
Theory of Mind
Self-Aware AI (still theoretical)

There are five main types as per AI literature, but in practice, these can be customized or hybridized for specific applications.

An AI agent is a computer system that perceives its environment, makes decisions, and performs actions to achieve goals.

Siri (Goal-Based Agent)
Thermostat (Model-Based)
Netflix recommender (Learning Agent)
Vending Machine (Simple Reflex)

You can download categorized AI agent guides and explanations from research publications and university courses.

Agents are entities in AI systems that perform autonomous tasks, guided by logic, learning, or goals.

ChatGPT (Learning + Utility-Based)
Roomba (Simple + Goal-Based)
Tesla Autopilot (Model + Goal-Based)

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