Simple Ollama Chatbot Using LangChain

💬 Simple Ollama-Based Chatbot Using LangChain

This tutorial explains how to build a basic chatbot using Ollama and LangChain. The chatbot runs fully locally and generates responses using a local LLM.

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🧠 What This Chatbot Does

• ✔ Sends a text prompt to a local Ollama model
• ✔ Receives an AI-generated response
• ✔ Runs offline without APIs
• ❌ Does not store previous conversations

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📦 Required Libraries

To build this chatbot, you only need the following Python libraries:

• langchain
• langchain-community

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⬇ How to Install Required Libraries

Install LangChain and Ollama community support using pip:

pip install langchain langchain-community

Make sure Ollama is already installed on your system and running.

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📥 Download Required Ollama Model

This chatbot uses the llama3.2 model. Download it using:

ollama pull llama3.2

You can verify the model by running:

ollama run llama3.2

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🧠 Python Code: Simple Ollama Chatbot

Below is the complete Python script:

from langchain_community.llms import Ollama

# Initialize Ollama model
llm = Ollama(model="llama3.2")

# User query (no memory)
query = '''
hello how are you
can you please tell me what is ollama
'''

# Invoke model
print(llm.invoke(query))

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📌 How This Code Works

• Ollama(model="llama3.2") → Connects to the local LLM
• query → User input prompt
• llm.invoke() → Sends prompt and gets response

Each execution is independent, meaning:

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🚀 Use Cases

• ✔ Learning Ollama + LangChain basics
• ✔ Simple AI response generators
• ✔ Offline chatbot experiments
• ✔ Testing LLM outputs locally

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🔧 Limitations

• ❌ No conversation history
• ❌ No document awareness
• ❌ No memory or context retention

These limitations can be solved using LangChain Memory or RAG pipelines, which will be covered in advanced projects.

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🔚 Conclusion

This simple Ollama chatbot is the foundation for more advanced AI systems. Once you understand this, you can extend it with:

• 🧠 Chat memory
• 📄 Document-based Q&A
• 🌐 Web or API interfaces

Happy building with local AI 🚀