> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fluents.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Knowledge Bases

> Store documents your agents can search during a call, so they answer from your content instead of improvising.

A **knowledge base** is a collection of documents your agents can search while they
are talking. Without one, an agent answers from its prompt, and when the prompt does
not cover something it improvises. With one, it looks the answer up.

***

## Create one

Go to **Knowledge** and click **Create Knowledge Base**. All it asks for is a name.

<Note>
  Creation is not instant. You will see a message saying the knowledge base is
  scheduled for creation and to check back in a few minutes, and it will not appear in
  the list straight away. Nothing has gone wrong. Refresh after a minute or two.
</Note>

Name it after the questions it answers rather than the file it came from. "Returns and
refunds" is easier to reason about later than "policy-doc-v3".

***

## Add documents

Open the knowledge base and drag files onto the drop zone, or click it to browse.

Supported file types are **PDF, TXT, RTF, DOC, DOCX, PPT, PPTX and HTML**.

<Warning>
  Spreadsheets are not supported. There is no CSV, XLS or XLSX. If your content lives
  in a spreadsheet, export it to one of the formats above first.
</Warning>

Uploaded files are listed with an ID and a name.

***

## Let an agent use it

Creating a knowledge base does not connect it to anything. Open the agent, go to the
**Data** tab, find **Knowledge Bases**, and click **Add Knowledge Base**.

<Note>
  This is not under **Choose Skills**, which is where most agent abilities live. It is
  on the **Data** tab.
</Note>

Each attachment asks **When should this be used?**, and that answer is what decides
when the agent searches. It is an instruction, not a label. Write it as the list of things a
customer might ask about, in their words. A vague description means the agent never
searches and answers from the prompt instead.

The **[Knowledge Search](./skills/knowledge-search)** page covers this in full.

***

## What to put in

Documents written for people to read work better than documents written for filing.

* **Prefer answers over policy.** A page that says what happens is more useful than
  one that says what the rules are.
* **Split by topic.** Several focused knowledge bases with clear descriptions beat one
  large one, because the description is what routes the search.
* **Leave out anything you would not want read aloud.** The agent is speaking, not
  linking.

***

## Where to go next

* Connect it to an agent: **[Knowledge Search](./skills/knowledge-search)**
* Check the agent actually searches when it should: **[Testing an agent](/product/features/agent-testing)**
* Put stable instructions in the prompt instead: **[Prompts](./prompts)**


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