💲 元属性

元属性是默认存在于 Port 中每个实体上的属性。

元属性总是在其前面使用美元符号 ($)来引用，这样可以更容易地分辨一个属性是用户定义的还是元属性。

下表列出了所有可用的元属性:

Meta-property	Description	Notes

| $identifier | Unique Entity identifier, used for API calls, programmatic access and distinguishing between different entities | | $title | A human-readable name for the entity | | | $team | The team this entity belongs to| | | $icon | The entity's icon | | | $createdAt | The entity's creation time | Value is set upon creation and never changes | | $updatedAt | The entity's last update time | Value is updated automatically | | $createdBy | The user who created the entity | Value is set upon creation and never changes | | $updatedBy | The user who last updated the entity | Value is updated automatically | | $blueprint | The entity's blueprint | |