{
  "id": "foaf",
  "acronym": "FOAF",
  "name": "Friend of a Friend",
  "category": "metadata",
  "domains": [
    "humanities",
    "computing"
  ],
  "kind": "vocabulary",
  "description": "FOAF is a project devoted to linking people and information using the Web. Regardless of whether information is in people's heads, in physical or digital documents, or in the form of factual data, it can be linked. FOAF integrates three kinds of network: social networks of human collaboration, friendship and association; representational networks that describe a simplified view of a cartoon universe in factual terms, and information networks that use Web-based linking to share independently published descriptions of this inter-connected world.",
  "formats": [
    "RDF",
    "JSON-LD"
  ],
  "license": "CC-BY-1.0",
  "homepage": "http://xmlns.com/foaf/spec",
  "download": "http://xmlns.com/foaf/0.1/",
  "bioportal": "FOAF",
  "bioregistry": "foaf",
  "registryStats": {
    "lov": {
      "reusedByVocabularies": 318,
      "reusedByDatasets": 249,
      "occurrencesInDatasets": 42362956,
      "modified": "2014-01-14",
      "namespace": "http://xmlns.com/foaf/0.1/"
    },
    "discovery": {
      "terms": 75,
      "triples": 620
    }
  },
  "publications": [],
  "usedBy": [],
  "tags": [
    "digital planning and construction",
    "ess",
    "fid baudigital",
    "nfdi4ing",
    "ontology",
    "people"
  ],
  "url": "https://schemascope.org/o/foaf/",
  "evaluation": {
    "links": {
      "homepage": {
        "url": "http://xmlns.com/foaf/spec",
        "code": 0,
        "state": "dead",
        "error": "fetch failed",
        "checkedAt": "2026-10-26T02:56:09.358Z"
      },
      "repository": null,
      "download": {
        "url": "http://xmlns.com/foaf/0.1/",
        "code": 200,
        "state": "ok",
        "resolvedUrl": "https://xmlns.com/foaf/0.1/",
        "lastModified": "2026-01-23T23:02:50.000Z",
        "checkedAt": "2026-10-26T02:55:48.887Z"
      }
    },
    "github": null,
    "ols": null,
    "obo": null,
    "bioportal": null,
    "citations": [],
    "git": null,
    "tib": {
      "portal": "TIB Terminology Service",
      "id": "foaf",
      "api": "v1",
      "title": "Friend of a Friend (FOAF) vocabulary",
      "iri": "http://xmlns.com/foaf/0.1/",
      "versionIri": null,
      "version": null,
      "releaseDate": null,
      "terms": 21,
      "properties": 71,
      "individuals": 0,
      "importsFrom": [],
      "exportsTo": [],
      "languages": [],
      "loaded": "2024-04-03T22:08:53.091+0000",
      "status": "SKIP",
      "page": "https://service.tib.eu/ts4tib/ontologies/foaf",
      "source": "https://service.tib.eu/ts4tib/api/ontologies/foaf",
      "fetchedAt": "2026-10-26T02:56:09.851Z"
    },
    "dashboard": null,
    "quality": {
      "reasoner": "ELK",
      "robotVersion": "ROBOT version 1.9.7",
      "consistent": null,
      "reasonError": "Not a valid (absolute) IRI: @context\nUse the -vvv option to show the stack trace.\nUse the --help option to see usage information.\n",
      "owl2dl": false,
      "checkedAt": "2026-10-25T21:55:22.239Z",
      "sha256": "eecbe127c9a3878f77df5f96dc77dce10ad7909b344be71e752b599386bc25d6",
      "source": "data/quality/foaf.json"
    },
    "oops": {
      "error": "no pitfall scanner succeeded",
      "attempts": [
        "local OOPS!: Command failed: docker run --rm -v /var/folders/qc/ymnxqz0x7g70whhm9jqspd8r0000gn/T/schemascope-quality/foaf:/work schemascope/oops --input-file /work/ontology.owl\nPicked up JAVA_TOOL_OPTIONS: -Xmx4g\n",
        "Python scan: Command failed: /opt/anaconda3/bin/python3 /Users/tekrajchhetri/Documents/schemascope/scripts/pitfalls.py scan /var/folders/qc/ymnxqz0x7g70whhm9jqspd8r0000gn/T/schemascope-quality/foaf/ontology.owl\n"
      ],
      "checkedAt": "2026-10-25T21:55:24.028Z",
      "sha256": "eecbe127c9a3878f77df5f96dc77dce10ad7909b344be71e752b599386bc25d6",
      "source": "data/quality/foaf.json"
    },
    "releases": {
      "dates": [],
      "lastYear": 0,
      "from": null
    },
    "bioregistry": {
      "prefix": "foaf",
      "name": "Friend of a Friend",
      "mappings": {
        "aberowl": "FOAF",
        "biocontext": "foaf",
        "biolink.resource": "foaf",
        "bioportal": "FOAF",
        "lov": "foaf",
        "tib.ts": "foaf",
        "zazuko": "foaf"
      },
      "dependsOn": [],
      "appearsIn": [],
      "license": "CC-BY-1.0",
      "version": "0.99",
      "deprecated": false,
      "page": "https://bioregistry.io/foaf",
      "source": "https://bioregistry.io/api/registry/foaf",
      "fetchedAt": "2026-10-26T02:55:48.559Z"
    },
    "artifact": {
      "source": "https://xmlns.com/foaf/0.1/",
      "isRdf": true,
      "etag": "\"63eb-6491628083a80\"",
      "contentType": "application/ld+json",
      "fetchedAt": "2026-10-26T02:55:48.886Z"
    },
    "score": 35,
    "gross": 35,
    "earned": 35,
    "possible": 100,
    "qualityApplies": true,
    "penalty": {
      "score": 0,
      "reason": "no penalties (active)",
      "steps": [
        {
          "label": "Time since last activity",
          "pts": 0,
          "detail": "0.8 years → 4 × max(0, 0.8 − 1)"
        },
        {
          "label": "Inactive status",
          "pts": 0,
          "detail": "not archived, legacy or inactive"
        },
        {
          "label": "Consistency",
          "pts": 0,
          "detail": "not yet checked by a reasoner"
        }
      ]
    },
    "consistent": null,
    "grade": "E",
    "fair": 26,
    "breakdown": {
      "findable": {
        "score": 4,
        "max": 12,
        "steps": [
          {
            "label": "Persistent identifier (F1)",
            "pts": 0,
            "max": 4,
            "detail": "no PURL / w3id / DOI for the artefact"
          },
          {
            "label": "Indexed in services (F4)",
            "pts": 4,
            "max": 5,
            "detail": "3: TIB, BioPortal, Bioregistry"
          },
          {
            "label": "Citable reference (F2)",
            "pts": 0,
            "max": 3,
            "detail": "no reference publication listed"
          }
        ],
        "notes": [
          "Persistent identifier (F1): no PURL / w3id / DOI for the artefact",
          "Indexed in services (F4): 3: TIB, BioPortal, Bioregistry",
          "Citable reference (F2): no reference publication listed"
        ]
      },
      "accessible": {
        "score": 9,
        "max": 12,
        "steps": [
          {
            "label": "Homepage reachable",
            "pts": 0,
            "max": 3,
            "detail": "HTTP fetch failed"
          },
          {
            "label": "Artefact retrievable over HTTP(S) (A1)",
            "pts": 6,
            "max": 6,
            "detail": "download HTTP 200"
          },
          {
            "label": "Metadata persists in a registry (A2)",
            "pts": 3,
            "max": 3,
            "detail": "Bioregistry"
          }
        ],
        "notes": [
          "Homepage reachable: HTTP fetch failed"
        ]
      },
      "interoperable": {
        "score": 8,
        "max": 12,
        "steps": [
          {
            "label": "Formal machine-readable format (I1)",
            "pts": 5,
            "max": 5,
            "detail": "RDF, JSON-LD"
          },
          {
            "label": "Semantic-web IRIs (I2)",
            "pts": 3,
            "max": 3,
            "detail": "RDF, JSON-LD"
          },
          {
            "label": "References other vocabularies (I3)",
            "pts": 0,
            "max": 4,
            "detail": "no imported vocabularies found"
          }
        ],
        "notes": [
          "References other vocabularies (I3): no imported vocabularies found"
        ]
      },
      "reusable": {
        "score": 5,
        "max": 12,
        "steps": [
          {
            "label": "Clear license (R1.1)",
            "pts": 5,
            "max": 5,
            "detail": "CC-BY-1.0"
          },
          {
            "label": "Release provenance (R1.2)",
            "pts": 0,
            "max": 4,
            "detail": "no version in artefact, registry or release tags"
          },
          {
            "label": "Community standards (R1.3)",
            "pts": 0,
            "max": 3,
            "detail": "no independent compliance report (not on the OBO Dashboard)"
          }
        ],
        "notes": [
          "Release provenance (R1.2): no version in artefact, registry or release tags",
          "Community standards (R1.3): no independent compliance report (not on the OBO Dashboard)"
        ]
      },
      "quality": {
        "score": 0,
        "max": 20,
        "steps": [
          {
            "label": "Logical consistency",
            "pts": 0,
            "max": 10,
            "detail": "never checked by a reasoner"
          },
          {
            "label": "OWL 2 DL profile",
            "pts": 0,
            "max": 2,
            "detail": "outside OWL 2 DL"
          },
          {
            "label": "Upper-ontology alignment",
            "pts": 0,
            "max": 3,
            "detail": "no BFO/COB/DOLCE import found"
          },
          {
            "label": "Standard relations (RO)",
            "pts": 0,
            "max": 1,
            "detail": "does not import the Relation Ontology"
          },
          {
            "label": "ROBOT report: no errors",
            "pts": 0,
            "max": 2,
            "detail": "no ROBOT report available"
          },
          {
            "label": "ROBOT report: warning density",
            "pts": 0,
            "max": 1,
            "detail": "no ROBOT report available"
          },
          {
            "label": "Pitfall scan: no critical pitfalls",
            "pts": 0,
            "max": 1,
            "detail": "no pitfall scan or ROBOT report yet"
          }
        ],
        "notes": [
          "Logical consistency: never checked by a reasoner",
          "OWL 2 DL profile: outside OWL 2 DL",
          "Upper-ontology alignment: no BFO/COB/DOLCE import found",
          "Standard relations (RO): does not import the Relation Ontology",
          "ROBOT report: no errors: no ROBOT report available",
          "ROBOT report: warning density: no ROBOT report available",
          "Pitfall scan: no critical pitfalls: no pitfall scan or ROBOT report yet"
        ]
      },
      "maintenance": {
        "score": 5,
        "max": 16,
        "steps": [
          {
            "label": "Recency",
            "pts": 5,
            "max": 10,
            "detail": "2026-01-23 → 9.0 months (≤ 1 year)"
          },
          {
            "label": "Release cadence (12 months)",
            "pts": 0,
            "max": 6,
            "detail": "0 releases"
          }
        ],
        "notes": [
          "Recency: 2026-01-23 → 9.0 months (≤ 1 year)",
          "Release cadence (12 months): 0 releases"
        ]
      },
      "adoption": {
        "score": 4,
        "max": 16,
        "steps": [
          {
            "label": "Documented adopting projects",
            "pts": 0,
            "max": 7,
            "detail": "0 projects"
          },
          {
            "label": "Reused by other ontologies",
            "pts": 4,
            "max": 4,
            "detail": "318 vocabularies (LOV)"
          },
          {
            "label": "Community signal",
            "pts": 0,
            "max": 5,
            "detail": "max(stars 0 → 0, citations 0 → 0)"
          }
        ],
        "notes": [
          "Documented adopting projects: 0 projects",
          "Community signal: max(stars 0 → 0, citations 0 → 0)"
        ]
      }
    },
    "lastActivity": "2026-01-23T23:02:50.000Z",
    "adopterCount": 0,
    "reuseCount": 318,
    "importCount": 0,
    "registries": [
      "TIB",
      "BioPortal",
      "Bioregistry"
    ],
    "evaluatedVersion": {
      "label": "file of 2026-01-23",
      "from": "Last-Modified of the download",
      "value": "2026-01-23T23:02:50.000Z",
      "all": [
        {
          "label": "file of 2026-01-23",
          "from": "Last-Modified of the download",
          "value": "2026-01-23T23:02:50.000Z"
        }
      ]
    },
    "evaluatedAt": "2026-10-26T02:56:09.853Z",
    "runId": "2026-10-26T02-37-38Z",
    "adopters": []
  },
  "history": [
    {
      "runId": "2026-10-26T02-37-38Z",
      "at": "2026-10-26T03:31:18.947Z",
      "score": 35,
      "grade": "E",
      "fair": 26,
      "version": "file of 2026-01-23",
      "terms": null,
      "stars": null,
      "license": null,
      "lastActivity": "2026-01-23T23:02:50.000Z",
      "adopters": 0,
      "links": {
        "homepage": "dead",
        "download": "ok"
      },
      "archived": false,
      "rubric": "3.4",
      "snapshot": "https://schemascope.org/runs/2026-10-26T02-37-38Z.json"
    }
  ],
  "changes": [],
  "recordProvenance": {
    "source": "harvest",
    "retrievedAt": "2026-10-25T22:04:44Z",
    "registries": [
      {
        "registry": "Bioregistry",
        "key": "bioregistry",
        "id": "foaf",
        "url": "https://bioregistry.io/api/registry/foaf",
        "retrievedAt": "2026-10-25T21:49:00Z"
      },
      {
        "registry": "TIB Terminology Service",
        "key": "tib",
        "id": "foaf",
        "url": "https://terminology.tib.eu/ts/ontologies/foaf",
        "retrievedAt": "2026-10-25T21:49:00Z"
      },
      {
        "registry": "Linked Open Vocabularies (LOV)",
        "key": "lov",
        "id": "foaf",
        "url": "https://lov.linkeddata.es/dataset/lov/vocabs/foaf",
        "retrievedAt": "2026-10-25T21:49:00Z"
      },
      {
        "registry": "Discovered via prefix.cc",
        "key": "discovery",
        "id": "foaf",
        "url": "http://prefix.cc/foaf",
        "artefact": "http://xmlns.com/foaf/0.1/",
        "retrievedAt": "2026-10-25T22:04:44Z"
      }
    ],
    "fields": {
      "acronym": "Bioregistry",
      "name": "Bioregistry",
      "description": "Bioregistry",
      "homepage": "Bioregistry",
      "download": "Bioregistry",
      "formats": "Bioregistry",
      "license": "Bioregistry",
      "bioportal": "Bioregistry",
      "tags": "Bioregistry"
    },
    "overrides": {
      "download": "http://xmlns.com/foaf/0.1/",
      "formats": [
        "RDF",
        "JSON-LD"
      ],
      "kind": "vocabulary",
      "acronym": "FOAF"
    },
    "overridesNote": "curated by SchemaScope, takes precedence over registry values"
  },
  "evaluationProvenance": {
    "@context": {
      "prov": "http://www.w3.org/ns/prov#",
      "schemascope": "https://schemascope.org/ns#"
    },
    "@id": "https://schemascope.org/o/foaf/#evaluation",
    "@type": "prov:Entity",
    "prov:specializationOf": {
      "@id": "http://xmlns.com/foaf/0.1/",
      "schemascope:evaluatedVersion": "2026-01-23T23:02:50.000Z"
    },
    "prov:wasGeneratedBy": {
      "@id": "https://schemascope.org/runs/2026-10-26T02-37-38Z",
      "@type": "prov:Activity",
      "prov:startedAtTime": "2026-10-26T02:37:38.997Z",
      "prov:endedAtTime": "2026-10-26T03:31:18.947Z",
      "prov:wasAssociatedWith": {
        "@id": "https://schemascope.org/ns#evaluator",
        "@type": "prov:SoftwareAgent",
        "schemascope:version": "2.0.0"
      },
      "prov:used": [
        {
          "@id": "http://xmlns.com/foaf/spec",
          "prov:atTime": "2026-10-26T02:56:09.358Z"
        },
        {
          "@id": "http://xmlns.com/foaf/0.1/",
          "prov:atTime": "2026-10-26T02:55:48.887Z"
        },
        {
          "@id": "https://xmlns.com/foaf/0.1/",
          "prov:atTime": "2026-10-26T02:55:48.886Z"
        },
        {
          "@id": "https://service.tib.eu/ts4tib/api/ontologies/foaf",
          "prov:atTime": "2026-10-26T02:56:09.851Z"
        },
        {
          "@id": "https://bioregistry.io/api/registry/foaf",
          "prov:atTime": "2026-10-26T02:55:48.559Z"
        }
      ]
    },
    "prov:generatedAtTime": "2026-10-26T02:56:09.853Z"
  }
}