> For the complete documentation index, see [llms.txt](https://renownedgames.gitbook.io/ai-tree/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://renownedgames.gitbook.io/ai-tree/perception-system/useful-nodes.md).

# Useful Nodes

This section covers useful nodes for working with [Perception System](/ai-tree/perception-system/quick-start.md) from [Behaviour Tree](/ai-tree/basic/behaviour-tree.md).

{% content-ref url="/pages/Ogo1FQAAgKMCSOFoho5z" %}
[Detection Signal](/ai-tree/nodes/tasks/perception-system/detection-signal.md)
{% endcontent-ref %}