glam/schemas/20251121/linkml/modules/classes/DigitalPlatform.yaml

id: https://nde.nl/ontology/hc/class/digital-platform
name: digital_platform_class
title: DigitalPlatform Class
imports:
- linkml:types
- ./Custodian
- ./CustodianObservation
- ./ReconstructionActivity
- ./DigitalPlatformType
- ./DigitalPlatformTypes
- ./AuxiliaryDigitalPlatform
- ./TimeSpan
- ./CollectionManagementSystem
- ./DataServiceEndpoint
- ./OAIPMHEndpoint
- ./SearchAPI
- ./METSAPI
- ./FileAPI
- ./IIPImageServer
- ./EADDownload
- ../slots/auxiliary_platforms
- ../slots/has_or_had_powered_by_cm
- ../slots/has_or_had_access_restriction
- ../slots/preservation_level
- ../slots/has_or_had_api_endpoint
- ../slots/metadata_standard
- ../slots/sparql_endpoint
- ../slots/oai_pmh_endpoint
- ../slots/platform_type
- ../slots/platform_name
- ../slots/storage_location
- ../slots/serves_finding_aid
- ./ReconstructedEntity
- ../slots/has_or_had_data_service_endpoint
- ../slots/collection_web_address
- ../slots/fixity_check_date
- ../slots/homepage_web_address
- ../slots/iiif_support
- ../slots/inventory_web_address
- ../slots/linked_data
- ../slots/platform_id
- ../slots/programming_language
- ../slots/refers_to_custodian
- ../slots/repository_software
- ../slots/specificity_annotation
- ../slots/template_specificity
- ../slots/temporal_extent
- ../slots/was_derived_from
- ../slots/was_generated_by
- ./SpecificityAnnotation
- ./TemplateSpecificityScores
prefixes:
  linkml: https://w3id.org/linkml/
  hc: https://nde.nl/ontology/hc/
  schema: http://schema.org/
  foaf: http://xmlns.com/foaf/0.1/
  dcat: http://www.w3.org/ns/dcat#
  dcterms: http://purl.org/dc/terms/
  crm: http://www.cidoc-crm.org/cidoc-crm/
  doap: http://usefulinc.com/ns/doap#
  premis: http://www.loc.gov/premis/rdf/v3/
  prov: http://www.w3.org/ns/prov#
classes:
  DigitalPlatform:
    is_a: ReconstructedEntity
    class_uri: schema:WebSite
    description: |
      Digital platform or online system associated with a heritage custodian.

      **CRITICAL DISTINCTION**:

      **DigitalPlatform CLASS** (this class):
      - Represents the DIGITAL INFRASTRUCTURE of any custodian
      - Used by PHYSICAL institutions (museums, archives, libraries) to represent their websites
      - Used by DIGITAL-FIRST institutions to represent their primary platform
      - Examples: Rijksmuseum website, museum online catalog, archive digital portal

      **DigitalPlatformType** (custodian type):
      - Classification for DIGITAL-FIRST custodians (online-only, no physical building)
      - Example: Europeana (aggregation platform), Internet Archive (born-digital)

      **Decision Rules**:

      1. **Physical Institution with Website**:
         - Custodian.custodian_type = MUSEUM/ARCHIVE/LIBRARY (not DIGITAL_PLATFORM)
         - Custodian.digital_platform → DigitalPlatform instance (this class)
         - Example: Rijksmuseum (MUSEUM) has Rijksstudio (DigitalPlatform)

      2. **Digital-First Institution**:
         - Custodian.custodian_type = DIGITAL_PLATFORM (DigitalPlatformType)
         - Custodian.digital_platform → DigitalPlatform instance (primary platform)
         - Example: Europeana (DIGITAL_PLATFORM) operates at https://europeana.eu/

      **Relationship to Custodian Hub**:

      DigitalPlatform is DIRECTLY connected to Custodian via refers_to_custodian,
      just like CustodianPlace, CustodianName, and CustodianLegalStatus.

      This allows modeling:
      - Multiple digital platforms per custodian (website + API + mobile app)
      - Platform evolution over time (temporal validity)
      - Platform features and technical capabilities
      - Access points for digital heritage

      - Schema.org: schema:WebSite (primary), schema:WebApplication
      - DCAT: dcat:Catalog (for aggregation platforms), dcat:DataService (for APIs)
      - FOAF: foaf:homepage, foaf:Document
      - CIDOC-CRM: crm:E73_Information_Object (digital objects)

      **Example - Physical Museum with Digital Platform**:
      ```yaml
      Custodian:
        hc_id: "https://nde.nl/ontology/hc/nl-nh-ams-m-rm-q190804"
        preferred_label: "Rijksmuseum"
        custodian_type: MUSEUM  # Physical institution
        digital_platform:
          - platform_name: "Rijksmuseum Website"
            homepage_web_address: "https://www.rijksmuseum.nl/"
            platform_type: DISCOVERY_PORTAL
            iiif_support: true
            linked_data: true
      ```

      **Example - Digital-First Platform**:
      ```yaml
      Custodian:
        hc_id: "https://nde.nl/ontology/hc/eu-europeana"
        preferred_label: "Europeana"
        custodian_type: DIGITAL_PLATFORM  # Digital-first
        digital_platform:
          - platform_name: "Europeana Platform"
            homepage_web_address: "https://www.europeana.eu/"
            platform_type: AGGREGATION_PLATFORM
            api_endpoint: "https://api.europeana.eu/"
            iiif_support: true
            linked_data: true
            programming_languages: ["Java", "Python", "JavaScript"]
      ```      
    exact_mappings:
    - schema:WebSite
    - foaf:homepage
    close_mappings:
    - schema:WebApplication
    - schema:SoftwareApplication
    - dcat:Catalog
    - dcat:DataService
    - crm:E73_Information_Object
    - doap:Project
    - premis:IntellectualEntity
    related_mappings:
    - foaf:Document
    - schema:SoftwareApplication
    - dcat:accessURL
    slots:
    - has_or_had_access_restriction
    - has_or_had_api_endpoint
    - auxiliary_platforms
    - collection_web_address
    - has_or_had_data_service_endpoint
    - fixity_check_date
    - homepage_web_address
    - iiif_support
    - inventory_web_address
    - linked_data
    - metadata_standard
    - oai_pmh_endpoint
    - platform_id
    - platform_name
    - platform_type
    - has_or_had_powered_by_cm
    - preservation_level
    - programming_language
    - refers_to_custodian
    - repository_software
    - serves_finding_aid
    - sparql_endpoint
    - specificity_annotation
    - storage_location
    - template_specificity
    - temporal_extent
    - was_derived_from
    - was_generated_by
    slot_usage:
      platform_id:
        slot_uri: dcterms:identifier
        description: |
          Unique identifier for this digital platform instance.
          Format: URI following NDE Heritage Custodian ontology conventions.          
        range: uriorcurie
        required: true
        identifier: true
        examples:
        - value: https://nde.nl/ontology/hc/platform/rijksmuseum-website
          description: Platform ID for Rijksmuseum website
      platform_name:
        slot_uri: schema:name
        description: |
          Human-readable name for this digital platform.

          Examples:
          - "Rijksmuseum Website"
          - "Europeana Platform"
          - "National Archives Digital Repository"
          - "Museum API"          
        range: string
        required: true
        examples:
        - value: Rijksmuseum Website
          description: Main website name
        - value: Europeana Platform
          description: Aggregation platform name
      platform_type:
        slot_uri: dcterms:type
        description: "Type of digital platform using DigitalPlatformType class hierarchy.\n\
          \n**Class-based Type System** (replaces DigitalPlatformTypeEnum):\n\nPlatform\
          \ types are organized into 8 high-level categories:\n- REPOSITORY: Digital\
          \ archives, libraries, institutional repositories\n- AGGREGATOR: Aggregation\
          \ and harvesting platforms  \n- DISCOVERY: Search portals, catalogs, discovery\
          \ interfaces\n- VIRTUAL_HERITAGE: 3D, VR/AR, immersive experiences\n- RESEARCH:\
          \ Research data platforms, annotation tools\n- INTERACTIVE: Crowdsourcing,\
          \ social, user contribution\n- COMMERCE: Licensing, print-on-demand, e-commerce\n\
          - AUXILIARY: APIs, mobile apps, specialized tools\n\nEach category contains\
          \ multiple concrete subclasses with Wikidata mappings.\nSee DigitalPlatformTypes.yaml\
          \ for 69 concrete platform types.\n\nA platform may have multiple types\
          \ (e.g., digital archive + aggregator).\n"
        range: DigitalPlatformType
        multivalued: true
        required: false
        examples:
        - value: DigitalArchivePlatform
          description: Digital archive platform (wd:Q1224984)
        - value: AggregationPlatform
          description: Aggregation platform (wd:Q7894)
      homepage_web_address:
        slot_uri: foaf:homepage
        description: |
          Primary homepage URL for this digital platform.

          FOAF: homepage for main web address.

          This is the entry point users access to interact with the platform.
          Must be a valid HTTP/HTTPS URL.          
        range: uri
        required: true
        pattern: ^https?://
        examples:
        - value: https://www.rijksmuseum.nl/
          description: Rijksmuseum homepage
        - value: https://www.europeana.eu/
          description: Europeana homepage
      collection_web_address:
        slot_uri: dcat:accessURL
        description: |
          URLs for accessing digital collections on this platform.

          DCAT: accessURL for collection access points.

          Examples:
          - "https://www.rijksmuseum.nl/nl/rijksstudio" (Rijksstudio collections)
          - "https://www.europeana.eu/en/collections" (Europeana collections browse)
          - "https://archive.org/details/texts" (Internet Archive text collections)          
        range: uri
        multivalued: true
        examples:
        - value: https://www.rijksmuseum.nl/nl/rijksstudio
          description: Rijksstudio collection access
      inventory_web_address:
        slot_uri: dcat:landingPage
        description: |
          URLs for archival inventories, finding aids, or collection catalogs.

          DCAT: landingPage for human-readable collection descriptions.

          Examples:
          - "https://www.nationaalarchief.nl/onderzoeken/index" (National Archives inventories)
          - "https://archief.amsterdam/inventarissen" (Amsterdam City Archives inventories)          
        range: uri
        multivalued: true
        examples:
        - value: https://www.nationaalarchief.nl/onderzoeken/index
          description: National Archives finding aids
      has_or_had_api_endpoint:
        slot_uri: dcat:endpointURL
        description: |
          API endpoint URL for programmatic access.

          DCAT: endpointURL for API base address.

          Examples:
          - "https://api.europeana.eu/record/v2/" (Europeana REST API)
          - "https://www.rijksmuseum.nl/api/" (Rijksmuseum API)
          - "https://archive.org/advancedsearch.php" (Internet Archive API)          
        range: uri
        examples:
        - value: https://api.europeana.eu/record/v2/
          description: Europeana REST API endpoint
      sparql_endpoint:
        slot_uri: dcat:endpointURL
        description: |
          SPARQL endpoint URL for linked data queries.

          DCAT: endpointURL for SPARQL service.

          Indicates platform supports RDF triple queries.

          Examples:
          - "https://api.europeana.eu/sparql" (Europeana SPARQL)
          - "https://data.collectienederland.nl/sparql" (Collectie Nederland SPARQL)          
        range: uri
        examples:
        - value: https://api.europeana.eu/sparql
          description: Europeana SPARQL endpoint
      oai_pmh_endpoint:
        slot_uri: dcat:endpointURL
        description: |
          OAI-PMH endpoint URL for metadata harvesting.

          DCAT: endpointURL for OAI-PMH service.

          Supports Open Archives Initiative Protocol for Metadata Harvesting.

          Examples:
          - "https://www.europeana.eu/oai" (Europeana OAI-PMH)
          - "https://repository.example.edu/oai" (Institutional repository OAI-PMH)          
        range: uri
        examples:
        - value: https://www.europeana.eu/oai
          description: Europeana OAI-PMH endpoint
      programming_language:
        slot_uri: doap:programming-language
        description: |
          Programming languages used to build this platform.

          DOAP: programming-language for software implementation languages.
          (DOAP = Description of a Project, W3C vocabulary for software projects)

          Examples:
          - "Java", "Python", "JavaScript", "Ruby", "PHP"
          - "TypeScript", "Go", "Rust"

          Useful for technical assessment and developer onboarding.          
        range: string
        multivalued: true
        examples:
        - value: Java
          description: Primary backend language
        - value: Python
          description: Data processing language
        - value: JavaScript
          description: Frontend language
      repository_software:
        slot_uri: doap:repository
        description: |
          Repository or content management software powering this platform.

          DOAP: repository for software/system identification.
          (DOAP = Description of a Project, W3C vocabulary for software projects)

          Examples:
          - "DSpace 7.x"
          - "Fedora Commons 6.x"
          - "CollectiveAccess"
          - "ResourceSpace"
          - "Omeka S"
          - "Custom-built"          
        range: string
        examples:
        - value: DSpace 7.2
          description: Digital repository software
      has_or_had_powered_by_cm:
        slot_uri: crm:P33i_was_used_by
        range: CollectionManagementSystem
        multivalued: true
        required: false
        description: "Collection Management System(s) powering this digital platform.\n\
          \nCIDOC-CRM: P33i_was_used_by (inverse of P33_used_specific_technique).\n\
          The CMS provides the backend/technique for the digital platform.\n\n**Bidirectional\
          \ Relationship**:\n- Forward: DigitalPlatform → CollectionManagementSystem\
          \ (powered_by_cms)\n- Reverse: CollectionManagementSystem → DigitalPlatform\
          \ (powers_platform)\n\n**Use Cases**:\n1. \"What CMS powers this website?\"\
          \ → Follow powered_by_cms\n2. \"What websites use CollectiveAccess?\" →\
          \ Follow powers_platform\n3. Technical assessment: Determine backend infrastructure\
          \ of platforms\n\n**Notes**:\n- Multivalued: Platform may use multiple CMS\
          \ (e.g., hybrid architecture)\n- If null, CMS may be unknown or platform\
          \ is custom-built\n- Distinct from repository_software: CMS is the full\
          \ system, \n  repository_software is the underlying software package\n"
        examples:
        - value: https://nde.nl/ontology/hc/cms/rijksmuseum-adlib
          description: Platform powered by Rijksmuseum's Adlib CMS
      iiif_support:
        slot_uri: dcterms:conformsTo
        description: |
          Does this platform support IIIF (International Image Interoperability Framework)?

          Dublin Core: conformsTo indicates standard compliance.
          When true, implies conformance to IIIF API specifications:
          - https://iiif.io/api/image/3/ (Image API 3.0)
          - https://iiif.io/api/presentation/3/ (Presentation API 3.0)

          IIIF enables:
          - Image API (deep zoom, tiles)
          - Presentation API (manifests, viewers)
          - Content Search API (full-text search)
          - Authentication API (access control)

          Boolean true/false or null if unknown.          
        range: boolean
        examples:
        - value: true
          description: Platform supports IIIF
        - value: false
          description: No IIIF support
      linked_data:
        slot_uri: dcterms:conformsTo
        description: |
          Does this platform provide linked open data (RDF)?

          Dublin Core: conformsTo indicates LOD compliance.

          Linked data features:
          - RDF triples (Turtle, JSON-LD, N-Triples)
          - SPARQL endpoint
          - Dereferenceable URIs
          - Linked to external vocabularies (Wikidata, Getty, etc.)

          Boolean true/false or null if unknown.          
        range: boolean
        examples:
        - value: true
          description: Platform provides linked data
        - value: false
          description: No linked data
      metadata_standard:
        slot_uri: dcterms:conformsTo
        description: |
          Metadata standards implemented by this platform.

          Dublin Core: conformsTo for standard compliance.

          Examples:
          - "Dublin Core"
          - "MARC21"
          - "EAD (Encoded Archival Description)"
          - "LIDO"
          - "MODS"
          - "EDM (Europeana Data Model)"
          - "Schema.org"
          - "CIDOC-CRM"          
        range: string
        multivalued: true
        examples:
        - value: Dublin Core
          description: Basic descriptive standard
        - value: MARC21
          description: Library catalog standard
      has_or_had_access_restriction:
        slot_uri: dcterms:accessRights
        description: |
          Access restrictions or rights management for this platform.

          Dublin Core: accessRights for access control.

          Examples:
          - "Public access"
          - "Registration required"
          - "Institutional access only"
          - "API key required"
          - "Subscription-based"
          - "Restricted to researchers"          
        range: string
        examples:
        - value: Public access
          description: Open to all users
        - value: API key required
          description: Developer registration needed
      has_auxiliary_platform:
        slot_uri: dcterms:hasPart
        description: |
          Subordinate or project-based digital platforms associated with this main DigitalPlatform.

          **DCAT Alignment**:

          `dcterms:hasPart` - Links main catalog/platform to sub-catalogs.

          **Hierarchical Pattern - Mirrors CustodianName/CustodianAppellation**:

          - DigitalPlatform (main entry point) → primary foaf:homepage
          - AuxiliaryDigitalPlatform (project sites) → secondary platforms

          Like CustodianAppellation provides alternative names for CustodianName,
          AuxiliaryDigitalPlatform provides subordinate platforms for DigitalPlatform.

          **Use Cases**:

          1. **Project Websites**: Research project portals, grant-funded sites
          2. **Exhibition Microsites**: Temporary exhibition portals, virtual tours
          3. **APIs and Tools**: Developer APIs, collection browsers, mobile apps
          4. **Legacy/Archived**: Previous website versions, deprecated systems
          5. **Educational Portals**: Teacher resources, learning modules

          **Example - Rijksmuseum**:
          ```yaml
          DigitalPlatform:
            platform_name: "Rijksmuseum Website"
            homepage_web_address: "https://www.rijksmuseum.nl/"
            has_auxiliary_platform:
              - platform_name: "Rijksstudio"
                auxiliary_platform_type: PROJECT_WEBSITE
              - platform_name: "Rijksmuseum Data API"
                auxiliary_platform_type: API_ENDPOINT
              - platform_name: "Night Watch Experience"
                auxiliary_platform_type: EXHIBITION_MICROSITE
          ```

          **Temporal Considerations**:

          Auxiliary platforms often have finite lifespans:
          - Exhibition microsite opens/closes with exhibition
          - Project portals run during funding period
          - Legacy platforms archived but accessible

          Each AuxiliaryDigitalPlatform tracks has_or_had_archival_status and archived_at.          
        range: AuxiliaryDigitalPlatform
        multivalued: true
        inlined_as_list: true
        required: false
        examples:
        - value:
          - platform_name: Rijksstudio
            auxiliary_platform_type: PROJECT_WEBSITE
            platform_url: https://www.rijksmuseum.nl/nl/rijksstudio
          - platform_name: Rijksmuseum Data API
            auxiliary_platform_type: API_ENDPOINT
            platform_url: https://data.rijksmuseum.nl/
          description: Rijksmuseum subordinate digital platforms
      temporal_extent:
        slot_uri: crm:P4_has_time-span
        description: |
          Temporal period during which this platform was operational.

          CIDOC-CRM: P4_has_time-span for platform lifecycle.

          Use when:
          - Platform launched (begin_of_the_begin)
          - Platform shut down (end_of_the_end)
          - Platform migrated to new URL

          For current platforms, leave end dates null.          
        range: TimeSpan
        examples:
        - value:
            begin_of_the_begin: '2008-11-20'
            end_of_the_begin: '2008-11-20'
          description: Europeana launched November 20, 2008
      was_derived_from:
        slot_uri: prov:wasDerivedFrom
        description: |
          CustodianObservation(s) documenting this platform.

          PROV-O: wasDerivedFrom for observation provenance.

          Examples:
          - Website screenshot observation
          - API documentation observation
          - Technical specification observation          
        range: CustodianObservation
        multivalued: true
        required: false
      was_generated_by:
        slot_uri: prov:wasGeneratedBy
        description: |
          ReconstructionActivity that created this platform record.

          PROV-O: wasGeneratedBy for generation activity.

          If present: Platform record created through formal reconstruction
          If null: Platform record extracted directly          
        range: ReconstructionActivity
        required: false
      refers_to_custodian:
        slot_uri: dcterms:references
        description: |
          The Custodian hub that operates this digital platform (REQUIRED).

          Links the digital platform to the custodian it represents.

          Dublin Core: references for entity reference.          
        range: Custodian
        required: true
        examples:
        - value: https://nde.nl/ontology/hc/nl-nh-ams-m-rm-q190804
          description: Rijksmuseum custodian hub
      preservation_level:
        slot_uri: premis:policy
        description: |
          Digital preservation commitment level for this platform.

          PREMIS: policy links to PreservationPolicy describing preservation actions.

          Values indicate the level of digital preservation applied:
          - "full_preservation": Complete digital preservation with format migration
          - "bit_preservation": Bit-level integrity preservation only
          - "access_only": No formal preservation commitment
          - "dark_archive": Preserved but not publicly accessible

          See Library of Congress PREMIS preservation levels:
          http://id.loc.gov/vocabulary/preservation/preservationLevelRole          
        range: string
        required: false
        examples:
        - value: full_preservation
          description: Complete digital preservation with format migration
        - value: bit_preservation
          description: Bit-level integrity preservation only
      storage_location:
        slot_uri: premis:storedAt
        description: |
          Primary storage location or infrastructure for digital content.

          PREMIS: storedAt links to StorageLocation describing where content is stored.

          Examples:
          - "AWS S3 eu-west-1" (cloud storage)
          - "On-premises data center, Amsterdam" (physical infrastructure)
          - "DANS Data Archive" (trusted digital repository)
          - "Internet Archive" (third-party preservation service)

          Note: For detailed storage information, use auxiliary properties
          or link to a dedicated StorageLocation entity.          
        range: string
        required: false
        examples:
        - value: AWS S3 eu-west-1
          description: Cloud storage in EU West region
        - value: DANS Data Archive
          description: Dutch trusted digital repository
      fixity_check_date:
        slot_uri: premis:fixity
        description: "Date of most recent fixity/checksum verification.\n\nPREMIS:\
          \ fixity property indicates integrity verification.\n\nRegular fixity checks\
          \ ensure digital content has not been \ncorrupted or altered. This date\
          \ indicates when the last \nverification occurred.\n\nBest practices recommend:\n\
          - Monthly fixity checks for actively accessed content\n- Quarterly checks\
          \ for archived content\n- Immediate verification after any storage migration\n"
        range: date
        required: false
        examples:
        - value: '2025-11-15'
          description: Last fixity check date
      serves_finding_aid:
        slot_uri: rico:isOrWasProviderOf
        range: uriorcurie
        multivalued: true
        inlined_as_list: true
        required: false
        description: |
          Finding aids hosted/served by this digital platform.

          **INVERSE RELATIONSHIP**:
          - Forward: FindingAid.served_by → DigitalPlatform (finding aid is served by platform)
          - Inverse: DigitalPlatform.serves_finding_aids → FindingAid[] (platform serves finding aids)

          **RiC-O ALIGNMENT**:
          `rico:isOrWasProviderOf` - The agent (platform) provides the finding aid.

          **USE CASES**:
          1. "What finding aids are available on this platform?" → Follow serves_finding_aids
          2. "Which platforms host EAD finding aids?" → Query platforms with EAD-format finding aids
          3. Platform inventory: Map all finding aids served by each digital infrastructure

          **EXAMPLES**:
          - National Archives website serves collection guides and inventories
          - Regional archive portal serves EAD-encoded finding aids          
        examples:
        - value: https://nde.nl/ontology/hc/finding-aid/na/voc-inventory
          description: VOC Archives inventory finding aid
        - value: https://nde.nl/ontology/hc/finding-aid/rm/paintings-catalogue
          description: Rijksmuseum paintings catalogue
      has_or_had_data_service_endpoint:
        slot_uri: dcat:servesDataset
        range: DataServiceEndpoint
        multivalued: true
        inlined_as_list: true
        required: false
        description: |
          Data service endpoints exposed by this digital platform.

          **DCAT ALIGNMENT**:
          `dcat:servesDataset` - Links a DataService to the datasets it serves.

          **ENDPOINT TYPES**:
          This polymorphic slot can contain any subclass of DataServiceEndpoint:
          - OAIPMHEndpoint: OAI-PMH metadata harvesting endpoints
          - SearchAPI: REST/JSON search API endpoints
          - METSAPI: METS document retrieval endpoints
          - FileAPI: File/asset download endpoints
          - IIPImageServer: IIP/IIIF image server endpoints
          - EADDownload: EAD finding aid download endpoints

          **USE CASES**:
          1. "What APIs does this platform expose?" → Follow data_service_endpoints
          2. "Which platforms support OAI-PMH?" → Filter by OAIPMHEndpoint type
          3. Technical integration: Discover all programmatic access points
          4. Data harvesting: Find endpoints for metadata aggregation

          **RELATIONSHIP TO SIMPLE SLOTS**:
          - `api_endpoint`, `sparql_endpoint`, `oai_pmh_endpoint` (simple URI slots) provide quick access
          - `data_service_endpoints` provides FULL documentation of each endpoint with:
            - Protocol details and versions
            - Authentication requirements
            - Rate limits and usage policies
            - Response formats and metadata standards
            - Discovery provenance

          **EXAMPLE - Nationaal Archief**:
          ```yaml
          has_or_had_data_service_endpoint:
            - endpoint_type: OAIPMHEndpoint
              endpoint_name: "NA OAI-PMH Endpoint"
              endpoint_url: "https://www.nationaalarchief.nl/onderzoeken/oai-pmh"
              protocol_version: "2.0"
              metadata_prefixes: ["oai_dc", "ese", "edm"]
            - endpoint_type: SearchAPI
              endpoint_name: "NA Search API"
              endpoint_url: "https://www.nationaalarchief.nl/onderzoeken/api/zoeken"
              http_method: POST
              response_formats: ["application/json"]
            - endpoint_type: IIPImageServer
              endpoint_name: "NA Image Server"
              endpoint_url: "https://service.archief.nl/iipsrv"
              server_software: "IIPImage Server"
              iiif_image_api_version: "3.0"
          ```          
        examples:
        - value:
          - endpoint_id: https://nde.nl/ontology/hc/endpoint/na-oai-pmh
            endpoint_name: Nationaal Archief OAI-PMH
            endpoint_url: https://www.nationaalarchief.nl/onderzoeken/oai-pmh
            protocol: OAI_PMH
            status: ACTIVE
          description: Nationaal Archief data service endpoints
      specificity_annotation:
        range: SpecificityAnnotation
        inlined: true
      template_specificity:
        range: TemplateSpecificityScores
        inlined: true
    comments:
    - DigitalPlatform is DIRECTLY linked to Custodian hub (not a subclass of CustodianObservation)
    - Used by BOTH physical institutions (website) and digital-first custodians (primary
      platform)
    - 'Multivalued on Custodian: one custodian can have multiple platforms (website
      + API + mobile app)'
    - Temporal validity tracks platform lifecycle (launch, shutdown, migration)
    - IIIF and linked data flags enable discovery of interoperable platforms
    - 'NEW: auxiliary_platforms links to subordinate AuxiliaryDigitalPlatform sites
      (project portals, microsites, APIs)'
    - Hierarchical pattern mirrors CustodianName → CustodianAppellation relationship
    see_also:
    - https://schema.org/WebSite
    - https://www.w3.org/ns/dcat
    - https://iiif.io/
    - http://usefulinc.com/ns/doap#
    - https://www.loc.gov/standards/premis/
    examples:
    - value:
        platform_id: https://nde.nl/ontology/hc/platform/rijksmuseum-website
        platform_name: Rijksmuseum Website
        platform_type:
        - DiscoveryPortal
        homepage_web_address: https://www.rijksmuseum.nl/
        collection_web_address:
        - https://www.rijksmuseum.nl/nl/rijksstudio
        api_endpoint: https://www.rijksmuseum.nl/api/
        iiif_support: true
        linked_data: true
        metadata_standard:
        - Dublin Core
        - LIDO
        access_restrictions: Public access, API key required for API
        refers_to_custodian: https://nde.nl/ontology/hc/nl-nh-ams-m-rm-q190804
      description: Rijksmuseum digital platform (physical museum with website)
    - value:
        platform_id: https://nde.nl/ontology/hc/platform/europeana
        platform_name: Europeana Platform
        platform_type:
        - AggregationPlatform
        - APIService
        homepage_web_address: https://www.europeana.eu/
        collection_web_address:
        - https://www.europeana.eu/en/collections
        api_endpoint: https://api.europeana.eu/record/v2/
        sparql_endpoint: https://api.europeana.eu/sparql
        oai_pmh_endpoint: https://www.europeana.eu/oai
        programming_language:
        - Java
        - Python
        - JavaScript
        iiif_support: true
        linked_data: true
        metadata_standard:
        - EDM (Europeana Data Model)
        - Dublin Core
        - LIDO
        - EAD
        access_restrictions: Public access, API key required for API
        temporal_extent:
          begin_of_the_begin: '2008-11-20'
          end_of_the_begin: '2008-11-20'
        refers_to_custodian: https://nde.nl/ontology/hc/eu-europeana
      description: Europeana platform (digital-first aggregation platform)
slots:
  platform_id:
    description: Unique identifier for the platform
    range: uriorcurie
  homepage_web_address:
    description: Primary homepage URL
    range: uri
  collection_web_address:
    description: Collection access URLs
    range: uri
  inventory_web_address:
    description: Inventory/finding aid URLs
    range: uri
  programming_language:
    description: Programming languages used
    range: string
  repository_software:
    description: Repository software used
    range: string
  iiif_support:
    description: IIIF support flag
    range: boolean
  linked_data:
    description: Linked open data flag
    range: boolean
  fixity_check_date:
    slot_uri: premis:fixity
    description: Date of most recent fixity/checksum verification
    range: date