If 2023 was the year everyone learned to prompt, then 2025 is the year everyone learns to build.
And guess what? You don’t need a PhD in computer science to build your first AI Agent anymore. Frameworks like LangChain and LangGraph make it simple, modular, and downright exciting.
In this tutorial, we’ll walk through the process of creating your first functional AI agent — one that can reason, plan, and take real-world actions.
Whether you’re a developer, tech hobbyist, or AI-curious freelancer — by the end of this guide, you’ll have your own working agent ready to roll.
🧩 Step 1: Understanding the Anatomy of an AI Agent
Before we start coding, let’s break down what makes an agentic system tick. Every functional AI agent includes:
LLM Core: The brain (e.g., GPT-4, Claude, Gemini, DeepSeek, etc.)
Memory: Stores context and history.
Tools: Connects the agent to external systems (APIs, databases, browsers).
Reasoning Engine: Determines what to do next.
Environment: The sandbox it operates in (e.g., local system, web, or cloud).
Think of it as building a mini employee — one that reads, thinks, and executes tasks independently.
⚙️ Step 2: Setting Up Your Development Environment
Requirements:
Python 3.10+
OpenAI API Key (or Anthropic, Gemini, etc.)
LangChain or LangGraph installed
# Install the essentials
pip install langchain openai
# OR
pip install langgraph
Optional Tools:
chromadb (for vector memory)
duckduckgo-search (for live search)
requests (for API calls)
🧠 Step 3: Building Your First LangChain Agent
Let’s build a simple research assistant that can search the web and summarize answers.
from langchain.llms import OpenAI
from langchain.agents import initialize_agent, load_tools
from langchain.agents import AgentType
# Step 1: Load your LLM
llm = OpenAI(temperature=0)
# Step 2: Load Tools
tools = load_tools(["serpapi", "llm-math"], llm=llm)
# Step 3: Initialize the Agent
agent = initialize_agent(
tools, llm, agent_type=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True
)
# Step 4: Run the Agent
response = agent.run("What are the top 3 AI agent frameworks in 2025?")
print(response)
What’s Happening:
The agent reasons about the query.
It uses the SerpAPI tool to fetch real data.
It reacts (plans → acts → reasons again).
Finally, it summarizes your answer intelligently.
Boom — you just created your first autonomous research agent. 🎉
🕸️ Step 4: Building Visually with LangGraph
If you prefer a visual and more structured approach, LangGraph is the evolution of LangChain — designed for multi-step reasoning and persistent memory.
Here’s what a simple LangGraph workflow might look like:
from langgraph.graph import Graph
from langgraph.nodes import LLMNode, ToolNode
# Define nodes
llm_node = LLMNode("chat", model="gpt-4")
tool_node = ToolNode("search", function=my_search_function)
# Create the graph
graph = Graph()
graph.add(llm_node)
graph.add(tool_node)
graph.connect(llm_node, tool_node)
# Run the graph
result = graph.run(input="Summarize the latest trends in Agentic AI.")
print(result)
LangGraph makes it possible to design multi-agent systems visually — perfect for complex workflows where multiple AIs collaborate.
🧠 Step 5: Giving Your Agent Memory
Memory is what transforms your AI from reactive to adaptive. It lets agents remember what they did and improve next time.
Using LangChain, you can easily add a memory component:
💡 Ready to go hands-on? Start building and testing your first Agentic AI workflows today at BestAIAgents.io — the ultimate builder’s hub for next-gen AI developers.