Last refreshed: 2026-07-06
Source: Identifiers shared structure, part of Linked Art API 1.0, published under CC BY 4.0. This is a project summary; the upstream page is authoritative.
Purpose
Identifiers are string codes assigned to a resource in a particular context, such as accession numbers, system identifiers, inventory numbers, or contact points. Every endpoint can use identifiers through `identified_by`.
Identifiers are structurally similar to Names, but they are not natural-language labels. They do not have `language`, translated forms, or alternative language forms.
Required Shape
An identifier structure includes:
- `type`: required. Must be `Identifier`.
- `content`: required string value of the identifier.
- `id`: optional URI identifying the identifier, not the entity being identified.
- `_complete`: optional completeness signal. If an `id` URI has richer dereferenceable information, `_complete: false` must be present.
Recommended Fields
- `_label`: developer-facing label.
- `classified_as`: classifications following the `Type` structure, such as accession number.
- `identified_by`: display names for the identifier itself, following the `Name` pattern.
Optional Fields
- `referred_to_by`: references to textual works about the identifier, or embedded statements about it.
- `assigned_by`: assignment evidence following the `AttributeAssignment` pattern.
Common Incoming Relationships
- `identified_by`: used by all endpoint records for identifiers assigned to the resource.
- `contact_point`: used by Person and Group records for contact points modeled as identifiers.
Meta Museum Notes
Meta Museum already preserves identifiers across object, concept, person, group, set, textual, visual, and digital records. Existing coverage proves primary/system identifiers and embedded `Identifier.assigned_by` evidence can survive record retrieval without being collapsed into display labels. Future fixture work should keep identifier assignment evidence explicit: `AttributeAssignment`, `timespan`, `carried_out_by`, and explanatory statements.
Test Ideas
- Preserve `Identifier.content` and `classified_as` for accession numbers and system identifiers.
- Preserve `identified_by` display names on identifiers without treating them as replacement identifier values.
- Preserve `referred_to_by` notes attached to identifiers.
- Preserve `assigned_by` `AttributeAssignment` evidence, including timespan and assigning group.
- Preserve `contact_point` identifiers on Person and Group records.
- Add a dereferenceable identifier `id` with richer detail available and verify `_complete: false`.