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

# Custom Properties

> Custom properties are documented together with datasource setup.

## Content moved

Custom property **schemas** (declared on the datasource via `object_definitions` → `property_definitions`) and **values** (sent as `custom_properties` on each document) are covered in one place:

<Card title="Datasource & custom properties" icon="database" href="/indexing-api/setup-datasource">
  Open the combined guide
</Card>

Quick links inside that page:

* [Custom attributes (property definitions)](/indexing-api/setup-datasource#custom-attributes-property-definitions)
* [Property definition fields](/indexing-api/setup-datasource#property-definition-fields)
* [Property types](/indexing-api/setup-datasource#property-types)
* [Sending values on documents](/indexing-api/index-documents#custom-properties-on-documents)
* [Schema validation & errors](/indexing-api/index-documents#schema-validation--errors)