---
title: Knowledge Base
description: "Gives the agent one knowledge base to consult for reference during conversations, chosen from the workspace's knowledge bases."
---

**Knowledge Base** gives the agent access to a knowledge base for reference during
conversations. The agent looks facts up in it when a question goes beyond the
prompt, and answers from what it finds instead of guessing.

:::tip[When to use it]
Anything too long or too changeable for the prompt: opening hours per branch, a
product catalogue, a policy document, an FAQ. Keep the prompt for who the agent is
and what it does; put what it needs to know in a knowledge base.
:::

![The Add Knowledge Base Tool dialog.](/media/build/knowledge-base-tool.webp)

## Configuring it

Open **Tools** under **Build**, choose **Add tool**, then **Knowledge Base**. Unlike
the other tools this one opens its own dialog, **Add Knowledge Base Tool**, with a
single field.

| Field | Type | Default | Notes |
|---|---|---|---|
| **Knowledge Base** | Select | `No knowledge base` (the tool will not use any knowledge base) | The workspace's knowledge bases, by name. Pick one. |

Choose the knowledge base, then **Close** the dialog and **Save** the agent.

The chosen knowledge base then shows above the tool list with a **Change** button.
To remove it, choose **Change** and pick **No knowledge base**.

Knowledge bases themselves are managed under **Knowledge Bases** in the main
sidebar. If the list in the dialog is empty, create one there first.

## In a flow agent

The knowledge base set with this tool is the agent's default. Each **Prompt** node
has a **KB** tab that can override it for that stage: tick one or more knowledge
bases there, or leave them all unticked to use the default. The node-level tool
picker does not offer **Knowledge Base**; the tab replaces it. See
[Nodes](/build/flow-agents/nodes#kb).

## Behaviour and limits

- One tool, one knowledge base. Add the tool once per agent.
- The agent decides when to look something up. Tell it in **Tasks** what the
  knowledge base covers: `Use the knowledge base for questions about prices,
  opening hours and insurance`.
- What the agent looks up is not stored in per-contact
  [memory](/build/memory); memory holds facts about the person, the knowledge base
  holds facts about you.
- Lookups appear as tool calls on the call's page. See
  [Call details](/operate/call-details).

## Related

- [Tools overview](/build/tools/overview)
- [Nodes](/build/flow-agents/nodes)
- [Memory](/build/memory)
- [Prompting guide](/build/prompting/prompting-guide)