Data, RAG & Self-Hosted AI tag | eYssen AI

18 Articles

Data, RAG & Self-Hosted AI ×

A Company Knowledge Chatbot: A Realistic Plan

Krisztian Eyssen, Krisztian Eyssen

A Company Knowledge Chatbot: A Realistic Plan

An airline's chatbot gave the wrong rules for its bereavement fare. The company's defence was that it is not responsible for "information provided by its agents, including a chatbot" — and it floated the idea that **the chatbot is a separate legal entity**. The court's answer is one sentence worth printing out: **"It makes no difference whether the information comes from a static page or from a chatbot."** The damages came to $812. The precedent is not so cheap.

Intermediate Business owner Recipe Data, RAG & Self-Hosted AI

Sep 13, 2026

How Do You Know Your RAG System Is Right?

Krisztian Eyssen, Krisztian Eyssen

How Do You Know Your RAG System Is Right?

At a public evaluation campaign a judge model was measured against a human assessor. Their agreement, corrected for chance, came out at **0.29**. On the very same task, **two humans agreed at −0.03** — worse than chance. So this is not a story of "the machine is bad, the human is good". The task itself is ill-defined at the edge cases. This article is about what can still be measured reliably.

Advanced Business owner How-To Data, RAG & Self-Hosted AI

Sep 13, 2026

Hybrid Search: Why Vectors Alone Are Not Enough

Krisztian Eyssen, Krisztian Eyssen

Hybrid Search: Why Vectors Alone Are Not Enough

In an academic measurement of 24 thousand questions, vector search scored **19.2%** on questions of the "who is [X]'s child?" type — the decades-old keyword algorithm scored **82.9%**. Sixty-three points apart. On a different set of questions the very same methods come out the other way round. **Neither one is better than the other: they have different failure modes.** Except that hybrid search is not what improves things most — re-ranking is.

Advanced Developer How-To Data, RAG & Self-Hosted AI

Sep 13, 2026

Vector Databases Without the Jargon

Krisztian Eyssen, Krisztian Eyssen

Vector Databases Without the Jargon

A widespread myth says the vector index eats a lot of memory. According to the vendor's own capacity-planning formula, **the graph is 5% of total memory** — 0.29 GB of index alongside 5.72 GB of vectors. It is the vectors that eat memory. And there is an even more important number: **ten thousand vectors are 75 megabytes.** That fits on a phone. So the question is not whether you need a separate vector database, but **when** — and the answer is usually "later than you think".

Intermediate Developer Explainer Data, RAG & Self-Hosted AI

Sep 13, 2026

Preparing and Chunking Your Documents

Krisztian Eyssen, Krisztian Eyssen

Preparing and Chunking Your Documents

In one measurement, simply cutting a long document into chunks lifts retrieval from **28.2 to 45.7** — **17.5 points for free**. The same measurement also shows that **bigger chunks are monotonically worse**. The awkward part: the most widely used tools ship with defaults of 800 and 1,024 tokens, or 4,000 characters — and in an independent test the 800-token setting finished **near the bottom of the field**.

Advanced Business owner How-To Data, RAG & Self-Hosted AI

Sep 13, 2026

Teaching AI Your Own Documents: RAG Explained

Krisztian Eyssen, Krisztian Eyssen

Teaching AI Your Own Documents: RAG Explained

Start with a 910-question benchmark: the same model scored **48.1%** out of the box, **50.4%** after fine-tuning, and **87.5%** with RAG. On another model fine-tuning did not help but **hurt** — from 35.3% down to 21.9%. So RAG is not one option among several: for new knowledge it is an order of magnitude better. It just happens **not to be teaching** — and most of the disappointment comes from believing that it is.

Intermediate Business owner Explainer Data, RAG & Self-Hosted AI

Sep 13, 2026 Bite-Sized AI

1
2

Follow Us

Archives

Tags

Audience

Everyone Office worker Marketer Creative Business owner Developer

Category

AI Basics Safety & Risk Regulation & Policy Infrastructure & Chips Business & Deals Prompting Models & Market Writing & Content Images & Design Video & Audio Marketing & SEO Coding & Development Work & Productivity Agents & Automation Data, RAG & Self-Hosted AI Business, Law & Security

Company

OpenAI Anthropic Google xAI (Grok) Meta Microsoft Mistral Chinese labs

Format

How-To Explainer Comparison Tool review Recipe Template Troubleshooting Case study Glossary News

Level

Beginner Intermediate Advanced

Tool

OpenRouter Perplexity HeyGen ElevenLabs Suno Obsidian MCP n8n Ollama EYAS

Others

Odoo