The significant leap in LLMs isn't just better text generation, but their ability to autonomously execute complex, sequential tasks. This 'agentic behavior' allows them to handle multi-step processes like scientific validation workflows, a capability earlier models lacked, moving them beyond single-command execution.

Unlike simple prompts that yield a single output, AI agents are systems that can execute a series of actions autonomously. They can develop a plan, use tools like the internet, and perform multiple steps to complete a complex task like running a marketing campaign.

An AI agent uses an LLM with tools, giving it agency to decide its next action. In contrast, a workflow is a predefined, deterministic path where the LLM's actions are forced. Most production AI systems are actually workflows, not true agents.

An AI feature like a chatbot requires turn-based user interaction. In contrast, a true AI agent is defined by its autonomy. It integrates with business systems (e.g., email, databases) to independently execute tasks and achieve a specified outcome without constant human input.

The true building block of an AI feature is the "agent"—a combination of the model, system prompts, tool descriptions, and feedback loops. Swapping an LLM is not a simple drop-in replacement; it breaks the agent's behavior and requires re-engineering the entire system around it.

Retrieval-Augmented Generation (RAG) is just one component of agent memory. A robust system must also handle dynamic operations like updating information, consolidating knowledge, resolving conflicts, and strategically forgetting obsolete data.

The 'call and response' nature of large language models (LLMs) is not truly revolutionary for workflows. The significant shift comes from agentic AI, which can connect to various systems and execute multi-step tasks. This moves AI from a content generator to a powerful workflow automation tool.

Classic RAG involves a single data retrieval step. Its evolution, "agentic retrieval," allows an AI to perform a series of conditional fetches from different sources (APIs, databases). This enables the handling of complex queries where each step informs the next, mimicking a research process.

At a technical level, an AI agent is a large language model that repeatedly calls itself. It uses provided tools to gather information and build its own context until it has enough data to achieve a predefined goal, making complex tasks autonomous.