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GuidesSep 9, 2026 · 7 min read

How to build an AI knowledge base for your business

Most knowledge bases get worse as they grow. Start from the twenty questions people actually ask, index in the right order, and test it before your customers do.

Hernan MoyaCo-Founder
A source list where two policies are indexed, a slide deck is skipped, and one question has nothing written behind it
A source list where two policies are indexed, a slide deck is skipped, and one question has nothing written behind it

Most knowledge bases get worse as they grow. The first ten documents answer well, and the hundredth makes the assistant vaguer instead of smarter.

That is not a scale problem. It is what happens when you index everything you own instead of what people actually ask.

Start from the questions, not the documents

The instinct is to point a crawler at the help centre and let it run. It is the wrong first move, because it decides what the assistant knows before anyone has decided what it needs to know.

Start with the twenty questions your team answers most often. Support inboxes, site search logs and the first five minutes of sales calls will give you all twenty in an afternoon.

Next to each question, write the document that answers it. Three kinds of row appear: a question with a good document behind it, a question with a document that half answers it, and a question nobody has ever written down.

That third kind is the most valuable thing you will produce this week.

InteractiveThe method, step by step
The gap is the point

A knowledge base cannot answer from a document that does not exist. Writing four short pages to close four gaps beats indexing four hundred pages that were never about the question.

What to index first, and what to leave for later

Documents are not worth the same to a retrieval system. Some were written as answers already. Others were written to persuade, or to be read with a person talking over them.

Source
When
Why
Help centre and FAQs
First
Already shaped as question and answer
Product documentation
First
Headings give every passage its context
Policies: returns, shipping, privacy
Early
High question volume, and they rarely change
Sales one-pagers
Later
Written to persuade, so claims outrun detail
Internal wikis and meeting notes
Later
They contradict each other and nobody notices
Slide exports
Rarely
Fragments without sentences retrieve badly

Six good documents will answer more questions than four hundred mediocre ones. Start narrow enough that you can read every answer the assistant gives.

The same team, the same content. The difference is what was left out.

Read your coverage before you index anything

The list of questions and sources is a map. Read it before you upload, because it tells you where the work is.

InteractiveTwenty questions, and what answers them

Green rows are ready to index. Amber rows need the document extended before it is worth indexing. Red rows are writing work, and no retrieval setting will substitute for them.

What breaks, and what it looks like when it does

Four failures cover almost everything that goes wrong in the first month.

What you see
What is actually wrong
What to do
It contradicts itself between two conversations
Two documents disagree and both are indexed
Merge them, or delete the older one
A confident answer that was true last quarter
Nothing marks a document stale
Give every source an owner and a review date
It quotes a table and gets the numbers wrong
The table lost its headers on import
Re-export as text, or rewrite the rows as sentences
A whole file returns nothing
The PDF is a scan, so there is no text to read
Run OCR before uploading it

The first row is the one teams argue about. The assistant is not being inconsistent; your documentation is, and until now nobody had a tool that read all of it at once.

Decide what does not go in

An assistant answers from whatever you feed it, to whoever can reach the widget. That is the whole value, and it is also the whole risk.

A public widget makes a document public

Anything indexed behind a widget on your site is effectively published. If it would not survive being on a page with no login, it does not belong in that knowledge base.

Salary bands, roadmaps, customer names and incident write-ups all read like ordinary documents to a crawler. The usual answer is two knowledge bases: one for the site, one for staff, with different widgets and different access.

Test it before your customers do

Your twenty questions are now a test set, which is the point of having written them down.

Ask all twenty and mark each answer right, wrong or partial. A first honest score is often around 14 / 20, and the six failures are more useful than the fourteen successes because each one names a specific cause.

Read the passages behind the wrong answers, not just the answers. A wrong answer built on a good passage means the document is wrong; a wrong answer built on a weak passage means retrieval missed.

welcomeai.devHow to fix bad retrieval scores by changing chunk size

Keep it from rotting

A knowledge base is not a project that finishes. The documents behind it change, and an index that does not follow them starts answering from last quarter.

  1. Connect the sources that change often, so edits arrive without an upload
  2. Re-run the twenty questions after any large content change
  3. Read the questions people asked that got no good answer, monthly
  4. Give every source an owner, because a document with no owner is a document nobody updates

The fourth one is the least technical and the most load-bearing.

Questions people ask

Write your twenty questions first, mark the ones nothing answers, and index only what is left. The gaps you find in that hour will do more for the assistant than any setting on the page.

Taggedknowledge-baseragretrievaldocumentationgetting-started
Written byHernan Moya

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