> For the complete documentation index, see [llms.txt](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/browsing-and-searching/snomed-ct-view/hierarchy.md).

# Hierarchy

You can expand and collapse the hierarchy by clicking the triangle in front of concepts. Expanding a node reveals the children of a concept, allowing you to browse down the hierarchy. As you continue to expand the children of a concept, you will eventually reach the end of the line with a concept that doesn't have any more children. These concepts have no triangle in front of them.

![Expanded SNOMED CT Tree](/files/BtnT5uufWDQdclDiJfOR)

The SNOMED CT hierarchical navigator visualizes the concept tree via the stated or the inferred `Is a` relationships. 

{% hint style="info" %}
You can switch between the two modes using the *Authoring* (:unlock:) icon in the application toolbar. 
{% endhint %}

Concept tooltips in the navigator display detailed information about the concept, including the ID, the Fully Specified Name, and the module. The number of descendants, if any, is also displayed

{% hint style="info" %}
To reveal the tooltip of a concept, just hover over it.
{% endhint %}

![SNOMED CT Tooltip](/files/oY70t8ZmlLuKJjXuOwT9)

{% hint style="info" %}
Fully defined concepts can be highlighted in bold by pressing the lightbulb toolbar icon.
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.b2ihealthcare.com/snow-owl-authoring-platform/browsing-and-searching/snomed-ct-view/hierarchy.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.