๐ต๏ธโโ๏ธ Unmasking the Truth Behind AI Agents, LLM Wrappers & How to Build One โ Scooby-Doo Style!

Table of contents
- ๐ค What Is an AI Agent?
- ๐ง How AI Agents Are Built (Architecture)
- ๐งฑ Popular Wrappers to Build Agents
- ๐ง Whatโs Inside the Agent (LLMs)
- ๐ ๏ธ Let's Build a Mini Agent (Code + Explanation)
- ๐ก What Just Happened?
- ๐ฆ Real Agent Use Cases
- ๐ฏ Recap: Build Your Own AI Agent (Steps)
- ๐ Bonus Resources
- ๐งต Want More?

Ever interacted with those AI agents that not only solve your problems but also chat like they're human?
Plot twist: Most of these โintelligentโ assistants are simply sophisticated wrappers around potent LLMs like GPT-4, Claude, or Gemini. ๐
Let's crack this case wide openโScooby-Doo style! Grab your magnifying glass and join us on a fun, mystery-solving journey into the inner workings of AI agents. ๐งฉ๐ถ
๐ค What Is an AI Agent?
An AI agent is a system that:
โ
Perceives its environment
โ
Decides what to do next
โ
Takes actions toward a goal
But IRL? Most agents are built by:
Prompting a powerful LLM
Giving it tools (like calculator, browser)
Adding memory (to remember stuff)
Using wrappers like LangChain to orchestrate everything
Itโs not magic. Itโs modular software. ๐ ๏ธ
๐ง How AI Agents Are Built (Architecture)
๐งโ๐ป UI โ Wrapper โ LLM โ Tools + Memory
Breakdown:
๐งโ๐ป UI: CLI, chatbot, or dashboard
๐งฉ Wrapper: LangChain, AutoGen = agentโs manager
๐ง LLM: GPT-4 = the brain
๐ง Memory: Pinecone, Chroma = remembers past chats
๐ง Tools: Search, API calls, calculator, file reader
๐งฑ Popular Wrappers to Build Agents
Wrapper | What It Does |
LangChain | Toolkit to build modular LLM apps & agents |
AutoGen | Framework for multi-agent chat + collab |
CrewAI | Role-based team agents that cooperate |
LlamaIndex | Helps agents work with private/custom data |
AgentVerse | Visual no-code playground for agents |
๐ง Whatโs Inside the Agent (LLMs)
Model | Provider | Superpowers |
GPT-4 | OpenAI | ๐ฅ Reasoning + tool usage |
Claude 3 | Anthropic | ๐ง Long context + ethical filters |
Gemini | ๐จ Multimodal: text + images | |
LLaMA | Meta | ๐ Open-source & community-driven |
Mistral | OSS | ๐จ Fast + lightweight |
๐ ๏ธ Let's Build a Mini Agent (Code + Explanation)
๐ฆ First, install the tools:
pip install langchain openai
๐ง Starter Code with Comments:
# basic_agent.py
from langchain.chat_models import ChatOpenAI
from langchain.agents import initialize_agent, Tool
from langchain.agents.agent_types import AgentType
import os
# โ
Set your OpenAI API key (required for GPT-4)
os.environ["OPENAI_API_KEY"] = "your-openai-key"
# ๐ง Define a custom tool (like a simple calculator)
def add_nums(a, b):
return str(int(a) + int(b)) # Returns a string (LangChain expects this)
# ๐ฆ Register the tool in LangChain
tools = [
Tool(
name="Adder",
func=lambda x: add_nums(*x.split()), # Parses "5 10" into a=5, b=10
description="Adds two numbers separated by a space"
)
]
# ๐ง Create the core LLM brain
llm = ChatOpenAI(model_name="gpt-4", temperature=0)
# ๐งฉ Create the agent and give it the tool
agent = initialize_agent(
tools, # Available tools
llm, # The LLM brain
agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, # Agent strategy
verbose=True # Show reasoning in the console
)
# ๐ฏ Ask the agent to solve a task using a tool
result = agent.run("Use the Adder tool to add 12 and 30.")
print(result)
๐ก What Just Happened?
๐ LangChain did the orchestration:
Understood the user query
โ "Use the Adder tool to add 12 and 30."Used GPT-4 to reason
โ โHmm, I should use the Adder tool.โCalled the
Adder
tool
โ Passed โ12 30โ โ Got42
Gave the final answer
So your agent appears smartโbut it's actually GPT-4 using tools you defined! ๐ ๏ธ๐ง
๐ฆ Real Agent Use Cases
๐ง AutoGPT โ Fully autonomous, recursive agents
๐ค AutoGen โ Multiple agents chatting together
๐ฌ Customer Bots โ Trained on FAQs/internal docs
๐งพ Research Agents โ Multi-step reasoning on documents
๐ฏ Recap: Build Your Own AI Agent (Steps)
Pick an LLM โ GPT-4, Claude, etc.
Pick a Wrapper โ LangChain, AutoGen
Add Tools โ Browser, APIs, etc.
Add Memory โ Pinecone, Chroma
Write Prompts โ Define behavior
Iterate โ Test, debug, improve
๐ Bonus Resources
๐ LangChain Docs
๐ง AutoGen GitHub
๐งฐ CrewAI GitHub
๐๏ธ LlamaIndex
๐พ Pinecone Vector DB
๐งต Want More?
Thinking of a follow-up on:
๐ LangChain Workflows
๐ง AutoGen Multi-Agent Chats
๐ Evaluating Agent Performance
Drop a ๐ in the comments & Iโll cook it up!
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Written by

Amit kumar Meena
Amit kumar Meena
Iโm a Computer Science student at NIT Warangal, passionate about coding, entrepreneurship, and self-improvement. I dive deep into software development, share insights on startups, and explore personal growth. Join me on my journey as I unravel the tech world and foster innovation through my blog.