What is an AI Agent?
An AI Agent is a software system that uses an AI model (usually an LLM) to understand a goal, decide what actions to take, use tools, and work toward completing a task.
Unlike a normal chatbot that primarily responds to questions, an AI Agent can take actions using APIs, databases, browsers, or other software systems.
1. Chatbot vs AI Agent
| Chatbot | AI Agent |
|---|---|
| Answers questions | Works toward completing goals |
| Primarily generates text | Generates text and performs actions |
| Usually responds to each prompt | Can execute multiple steps |
| Limited tool usage | Can use tools and APIs |
| Example: Explain an invoice | Example: Find unpaid invoices and prepare follow-ups |
An AI Agent typically works like this:
- Goal: User gives the agent a task.
- Reasoning: LLM analyzes the task and decides what to do.
- Planning: Agent determines the sequence of actions.
- Tool execution: Agent calls APIs, databases, or other tools.
- Observation: Agent checks the results.
- Iteration: It decides whether another action is required.
- Completion: Agent returns the result or completes the task.
The process may repeat several times until the goal is achieved or the agent needs human input.
3. Example: Banking AI Agent
Imagine creating an AI Agent for a banking application.
User asks:
Find my last 5 transactions and identify unusual payments.
The agent could perform:
User Request
LLM – Understand the request
Determines that transaction data must be retrieved.
Tool – Transaction API
Calls banking API to retrieve transactions.
LLM – Analyze transactions
Evaluates transaction details and potential anomalies.
Final Response
Explains findings to the user.
The AI Agent does not directly access the banking database by itself. It uses tools provided by the application, subject to authorization and security controls.
4. AI Agent Architecture
Typical components:
| Component | Responsibility |
|---|---|
| LLM | Reasoning and decision-making |
| Tools | APIs, database queries, functions |
| Memory | Retains relevant context |
| Planner | Determines steps to execute |
| Execution engine | Runs tools and manages workflow |
| Guardrails | Controls permissions and unsafe actions |
Not every AI Agent requires a separate planner or memory database. Simple agents can use an LLM with a few tools.
5. How to build an AI Agent using Java Spring Boot?
You can use Spring AI to build AI Agents.
Relevant technologies:
- Spring AI – AI integration framework for Spring Boot.
- Ollama – Run local LLMs.
- PostgreSQL + pgvector – Store embeddings and retrieve knowledge.
- REST APIs – Connect agents to business systems.
- MCP (Model Context Protocol) – Standardized way to expose tools and context to AI applications.
A basic architecture:
User
|
v
Spring Boot AI Agent
|
+—- LLM (Ollama / GPT)
|
+—- Banking APIs
|
+—- Database Tools
|
+—- Vector Database
|
v
Task Execution and Response
6. Difference between RAG and AI Agent
| RAG | AI Agent |
|---|---|
| Retrieves relevant information | Performs tasks |
| Uses knowledge documents | Uses tools and APIs |
| Provides context to LLM | Can decide which tools to invoke |
| Mainly knowledge-based | Action-oriented |
An AI Agent can also use RAG.
For example, a Backbase development agent could retrieve architecture documentation through RAG, inspect configuration files, analyze errors, and propose changes.
Final understanding
AI ecosystem in one line:
LLM = Intelligence
Embedding Model = Semantic representation
Vector Database = Knowledge retrieval
RAG = Knowledge grounding
AI Agent = Intelligence + Tools + Actions