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

# App Data Schemas

App Data Schemas is a [Data Schema](/docs/references/data-schemas) that can be shared across multiple places in your integrations.\
It can be used for [Field Mappings](/reference/workspace-elements/field-mappings) or as a component for any other schema used in an integration.

## Referencing Schema

You can reference an App Data Schema in other schemas using the `$ref` formula:

```json theme={null}
{
  "type": "object",
  "properties": {
    "name": { "type": "string" },
    "user": {
      "$ref": "schemas/user" // Reference to the "user" App Data Schema
    }
  }
}
```

## User-specific Schema

Whenever a schema is used in a context of a specific user, and you provided an HTTP request, it will be executed on behalf of the current user.

The response to this request should be a JSON-encoded [Data Schema](/docs/references/data-schemas).

You can find the latest request and response for a given user on the [App Data Schema Instances](https://console.integration.app/w/0/deployments/app-data-schema-instances) page.