AI & Generative AI

Generative AI went from research demo to everyday infrastructure faster than almost any technology before it. Large language models now draft code, answer support tickets, summarize documents, and drive autonomous agents — and the gap between "interesting demo" and "reliable product" comes down to engineering: grounding models in real data, constraining their outputs, and designing around their failure modes.

This hub is the practical path through that landscape — from how LLMs work, to prompting them well, to building retrieval and agent systems on top of AI APIs.

TL;DR

The Generative AI Stack

A useful way to see how the pieces fit, from model to application:

Featured Topics

Large Language Models

Prompt Engineering & Agents

RAG & Embeddings

AI APIs & Tools

Building for Production

Open-Source AI

Choosing Your Approach

The most common architectural question — prompting, RAG, or fine-tuning? — has a clear default order:

Start at the top and move down only when the simpler option falls short.

Common Questions

Where do I start building an AI feature?

With the simplest thing that works: a single, well-crafted API call. Add retrieval (RAG) when the model needs your private or current data, and reach for tool use or an agent only when the task genuinely requires the model to act over multiple steps. Most "AI features" are a good prompt plus, at most, RAG — not an autonomous agent.

How do I stop the model from making things up?

Ground it. Retrieval-augmented generation supplies real context the model must answer from, tool/function calling fetches authoritative data, and instructing the model to cite sources and say "I don't know" reduces confident fabrication. Validate critical outputs. You can lower hallucination dramatically but not eliminate it — design the product to tolerate and catch errors.

Which model should I use?

Match the tier to the task: a frontier model (e.g. Claude Opus 4.8) for the hardest reasoning and agentic work, a balanced model (Claude Sonnet 4.6) for most production workloads, and a fast/cheap model (Claude Haiku 4.5) for high-volume simple tasks. Prototype on a capable model to confirm the task is feasible, then optimize for cost/latency. See Large Language Models.

Do I need to train or fine-tune my own model?

Almost never to start. Frontier models are highly capable out of the box and adapt well through prompting and RAG — far cheaper and faster than training. Fine-tuning helps for narrow, high-volume tasks needing specific behavior or a smaller model, and only when you have quality labeled data. See Fine-Tuning.

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