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# ObjectId

Property Type: `objectid`

An ObjectId is a 12-byte BSON type, used to represent the `_id` property of contexts, posts, body segments, document array element identifiers, and others. When retrieved using the API, these values are represented in the response as a 24-byte hexadecimal string value.

### Property Validators

**Required**\
name: `required`

**ID Enum Validator**\
name: `idEnum`\
definition:

| Name   | Type    | Default | Description                                               |
| ------ | ------- | ------- | --------------------------------------------------------- |
| idEnum | boolean | true    | true if element exists in the list of possible objectId's |