Topic

AI Agents

Design practical AI agents that combine language models, tools, retrieval, and workflows.

How LLMs Work: From Tokens to AI Agents

Before you can build an AI agent, you need to understand the engine inside it. A ground-up walkthrough of LLMs — tokenization, transformers, training, and the limits that make agents necessary.

How to Actually Use LLMs in Your Daily Life

Practical ways to use ChatGPT, Claude, and Gemini — from clearing doubts and building resumes to brainstorming ML projects and automating content creation. Plus one critical warning about when not to reach for them.

Open-Source vs Paid LLMs: Which One Should You Use?

GPT, Claude, and Gemini aren't the only options. A clear breakdown of open-source vs paid models — what they are, how they differ, and a decision framework for choosing the right one for your use case.

Prompt Engineering: Zero-Shot vs Few-Shot Prompting

Getting bad or inconsistent outputs from an LLM usually isn't the model's fault — it's the prompt. Learn the two core prompting techniques, when to use each, and how few-shot examples unlock custom output formats.

ReAct and RAG: Giving LLMs Access to the External World

An LLM's knowledge stops at its training cutoff and it can't access your private data. ReAct and RAG are the two prompt engineering frameworks that fix both problems — turning a plain LLM into an agent that can act and retrieve.

RAG Deep Dive: Embeddings, Vector Search, and ChromaDB

RAG is how you give LLMs accurate answers from documents they've never seen. This post covers the full architecture: chunking, embeddings, similarity search, vector databases, and a working implementation with ChromaDB.

Building a RAG Pipeline with ChromaDB

A complete hands-on implementation of RAG using ChromaDB — persistent storage, collections, metadata filtering, custom embedding models, and a full end-to-end pipeline that answers questions from a private document.

RAG Chunking: Sentence-Based Splitting

Fixed-size chunking breaks sentences mid-word. Sentence-based chunking fixes that by treating each complete sentence as its own chunk — better context, better vectors, better retrieval.

RAG Chunking: Recursive Character Splitting

Recursive character splitting is the most practical chunking strategy for real documents — it respects natural boundaries like paragraphs and sentences, falls back gracefully, and uses overlap to preserve cross-boundary context.

RAG Chunking: Sliding Window Strategy

Sliding window chunking ignores paragraph and sentence boundaries entirely. Instead it moves a fixed-size window forward by a configurable stride — creating dense, overlapping chunks that preserve context across every split.

RAG Chunking: Semantic-Based Splitting

Every chunking strategy so far splits by size. Semantic chunking splits by meaning — grouping sentences that discuss the same topic into one chunk, regardless of character or word count.

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