How to Build Your First AI Agent in 2026 (Step-by-Step)

Prerequisites

• Python 3.12+
• OpenAI API Key
• Tavily API Key (for search)

Step 1: Setup

pip install langchain-openai langchain tavily-python

Step 2: The Code

from langchain.agents import initialize_agent, AgentType
from langchain_openai import ChatOpenAI
from langchain_community.tools.tavily_search import TavilySearchResults

# 1. Initialize LLM
llm = ChatOpenAI(model="gpt-4o", temperature=0)

# 2. Define Tools
tools = [TavilySearchResults(max_results=1)]

# 3. Create Agent
agent = initialize_agent(
    tools, 
    llm, 
    agent=AgentType.OPENAI_FUNCTIONS, 
    verbose=True
)

# 4. Run!
agent.run("Search for the latest AI news and summarize it.")

How It Works

1. Perception: The agent receives your command.
2. Reasoning: The LLM "thinks" and decides it needs to search.
3. Action: It calls the Tavily Search tool.
4. Observation: It reads the search results.
5. Response: It synthesizes the answer back to you.

Next Steps

To make this a true "Agent", give it more tools:

• File Write Access: To save reports.
• Email Access: To send summaries.
• Calendar Access: To schedule meetings.

Final Verdict