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

# SummerWorldDefinitionIdentity

> Immutable selected WorldDefinition projection.

**Class:** `SummerWorldDefinitionIdentity` · **Inherits:** RefCounted

Immutable selected WorldDefinition projection.

Identifies the exact composition contract selected by the platform for this World.

## Properties

| Property | Type | Access | Description |
| - | - | - | - |
| <a id="definition_id" />`definition_id` | String | read-only, `get_definition_id()` | Stable definition ID. |
| <a id="digest_sha256" />`digest_sha256` | String | read-only, `get_digest_sha256()` | Exact manifest digest when negotiated. |
| <a id="lifetime" />`lifetime` | [`SummerWorldDefinitionIdentity.Lifetime`](/api-reference/gdscript/types/world-definition-identity#lifetime) | read-only, `get_lifetime()` | World lifetime contract. |

## Enums and constants

### Lifetime

| Name | Value | Description |
| - | - | - |
| `LIFETIME_MATCH_SCOPED` | `0` | One Match per World. |
| `LIFETIME_PERSISTENT` | `1` | Persistent World with World-bound continuity. |
| `LIFETIME_MULTI_MATCH` | `2` | One World may host sequential Matches. |

***

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