> For the complete documentation index, see [llms.txt](https://dev.guardian.hedera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.guardian.hedera.com/guardian/standard-registry/schemas/system-schema-apis.md).

# System Schema APIs

Endpoints for managing Guardian system schemas — predefined schema types used internally by the platform.

**Authentication:** Bearer token required (`Authorization: Bearer <token>`)

***

| Method   | Endpoint                                     | Description                                   | Auth Required |
| -------- | -------------------------------------------- | --------------------------------------------- | ------------- |
| `GET`    | `/api/v1/schemas/system/{username}`          | Returns system schemas for the specified user | Yes           |
| `POST`   | `/api/v1/schemas/system/{username}`          | Creates a new system schema                   | Yes           |
| `DELETE` | `/api/v1/schemas/system/{schemaId}`          | Deletes a system schema                       | Yes           |
| `PUT`    | `/api/v1/schemas/system/{schemaId}`          | Updates a system schema                       | Yes           |
| `PUT`    | `/api/v1/schemas/system/{schemaId}/active`   | Publishes (activates) a system schema         | Yes           |
| `GET`    | `/api/v1/schemas/system/entity/{schemaType}` | Returns a system schema by type               | Yes           |

## Endpoints

* [Returns Schema by Username](/guardian/standard-registry/schemas/system-schema-apis/returns-schema-by-username.md)
* [Creates New System Schema](/guardian/standard-registry/schemas/system-schema-apis/creates-new-system-schema.md)
* [Delete System Schema](/guardian/standard-registry/schemas/system-schema-apis/delete-system-schema.md)
* [Updates the Schema](/guardian/standard-registry/schemas/system-schema-apis/updates-the-schema.md)
* [Publishes the Schema](/guardian/standard-registry/schemas/system-schema-apis/publishes-the-schema.md)
* [Returns Schema by Type](/guardian/standard-registry/schemas/system-schema-apis/returns-schema-by-type.md)
* [Schema Type](/guardian/standard-registry/schemas/system-schema-apis/schema-type.md)
* [Returns Map API Key](/guardian/standard-registry/schemas/system-schema-apis/returns-map-api-key.md)