> For the complete documentation index, see [llms.txt](https://developer.harness.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.harness.io/internal-developer-portal/3.0/working-with-apis/api-references/overview.md).

# API Overview

This document provides an overview of the different types of APIs available for Harness IDP. These APIs enable programmatic access and management of various entities within Harness IDP.

In Harness IDP there are two types of APIs that are being used

1. Backstage API
2. Platform API

### Backstage API <a href="#backstage-api" id="backstage-api"></a>

The Backstage API includes the Backstage endpoints exposed through the Harness Platform. This API lets you programmatically add/remove entities in the catalog. For detailed documentation on endpoints and other Backstage API reference information, go to the [Backstage API reference documentation](/internal-developer-portal/working-with-apis/api-references/public-api.md).

### Platform API <a href="#platform-api" id="platform-api"></a>

The Platform API provides native Harness IDP APIs within the Harness Platform. For detailed documentation on endpoints and other Harness IDP API reference information, go to the [Harness API reference documentation](https://apidocs.harness.io/tag/AppConfig).

#### Catalog ingestion API <a href="#catalog-ingestion-api" id="catalog-ingestion-api"></a>

Software Catalog in Harness IDP supports modifying metadata for the services, libraries, websites and any other entities registered in the Catalog using the [Catalog Ingestion API](/internal-developer-portal/3.0/use-idp/software-catalog/integrate-tools/catalog-ingestion-api.md).