---
category: [Administration & Integrations, Platform and Product Extensions, Platform and Product Extensions/Integration, Administration & Integrations/Custom Integrations & Apps, Platform and Product Extensions/Workday Extend]
keyword: [Extend, Presentation Components, UI components]
nav: wcp_docs
parent_url: /wcp_docs/
title: >- 
  Concept: Site Metadata
layout: subsection
---

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The Site Metadata (SMD) represents a site, which is a logical collection of pages within your app. The SMD contains declarations such as site authentication and custom error pages.

For details about the SMD properties and subschemas, see [Reference: Site Metadata](/wcp_docs/mwr1528410641805.html).

## <a id="section_siteAuth"></a>Site Authentication

The `siteAuth` subschema in the SMD defines authentication types used by the pages. Multiple definitions in the site authentication enable your app to fetch data from various REST API endpoints that require different authentication types. After you've defined the authentication types in the SMD, your app pages (PMDs) can reference the appropriate authentication type when invoking an endpoint request.

The populated authentication type is Workday Single-Sign On (SSO). Although you can't override the populated SSO authentication at the app level, you can specify the `authType` for each endpoint in the PMD.

## <a id="section_hw5_ylh_d2b"></a>Custom Error Pages

Custom error pages enable your app to respond to specific REST HTTP error response codes. Custom error pages enable you to provide custom messages and give guidance on how to recover from the problem.

## <a id="section_pgj_kzg_r4b"></a>Sample Apps

For sample SMDs, see the `smd` file of the sample apps using Presentation Components in the App Catalog.

### Related Information

[Reference: Extend App Metadata](/wcp_docs/btj1547749859781.html)

[Reference: PMD Tags](/wcp_docs/dyg1528862158582.html)

[Reference: Site Metadata](/wcp_docs/mwr1528410641805.html)

[App Catalog: Charitable Donations](/app-catalog/charitableDonations)