{
  "schema": "kallipolis.resource-quality.v1",
  "id": "resource.public-data.crossref-rest-api",
  "version": "1.0.0",
  "title": "Crossref REST API boundary",
  "summary": "Official-source access, authentication, request-shaping, paging, freshness, legal, and interpretation boundaries for Crossref REST API.",
  "content": {
    "kind": "public-data-api-boundary",
    "facts": [
      {
        "id": "fact.crossref.rest-api.access",
        "statement": "Crossref's REST API exposes member-deposited scholarly metadata through works, journals, members, funders, licenses, prefixes, and type endpoints.",
        "normativeLevel": "informative",
        "sourceIds": [
          "source.crossref.rest-api"
        ]
      },
      {
        "id": "fact.crossref.rest-api.authentication",
        "statement": "Public access requires no signup; polite and paid pools use identification or authentication and have distinct rate and concurrency limits.",
        "normativeLevel": "informative",
        "sourceIds": [
          "source.crossref.rest-api"
        ]
      },
      {
        "id": "fact.crossref.rest-api.request",
        "statement": "Large retrievals should use filters, cursors, bounded date windows, caching, and backoff rather than assuming an unbounded stable result set.",
        "normativeLevel": "informative",
        "sourceIds": [
          "source.crossref.rest-api"
        ]
      },
      {
        "id": "fact.crossref.rest-api.boundary",
        "statement": "Metadata can include publisher-provided abstracts and full-text links, but a link does not guarantee full-text access, accuracy, copyright permission, or completeness.",
        "normativeLevel": "informative",
        "sourceIds": [
          "source.crossref.rest-api"
        ]
      }
    ]
  },
  "language": "en",
  "category": "public-data-api",
  "state": "prepared",
  "canonicalUrl": "https://platoskallipolis.com/resources/public-data-apis/crossref-rest-api.json",
  "contentHash": "sha256:6191aa4bd34ea3fcad467c110423b72130a5d002b688220ecb3e99b095584614",
  "owner": {
    "id": "platos-kallipolis",
    "name": "Plato's Kallipolis",
    "type": "organization",
    "accountabilityUrl": "https://platoskallipolis.com/about"
  },
  "access": {
    "mode": "public",
    "url": "https://platoskallipolis.com/resources/public-data-apis/crossref-rest-api.json",
    "authentication": "none",
    "robotsAllowed": true
  },
  "provenance": {
    "method": "primary-source",
    "sources": [
      {
        "id": "source.crossref.rest-api",
        "url": "https://www.crossref.org/documentation/retrieve-metadata/rest-api/",
        "title": "Crossref REST API",
        "publisher": "Crossref",
        "observedAt": "2026-08-27T08:40:00Z"
      }
    ]
  },
  "observedAt": "2026-08-27T08:40:00Z",
  "freshness": {
    "policy": "max-age",
    "state": "current",
    "nextReviewAt": "2026-09-03T08:40:00Z",
    "maxAgeSeconds": 604800
  },
  "license": {
    "id": "source-terms-apply",
    "url": "https://www.crossref.org/documentation/retrieve-metadata/rest-api/access-and-authentication/",
    "redistributionAllowed": false
  },
  "evidence": [
    {
      "id": "evidence.crossref.rest-api",
      "type": "source-claim",
      "url": "https://www.crossref.org/documentation/retrieve-metadata/rest-api/",
      "observedAt": "2026-08-27T08:40:00Z"
    }
  ]
}