specification: API Commons Conformance specificationVersion: '0.1' provider: Appalachian Regional Commission providerId: appalachian-regional-commission generated: '2026-09-07' method: probed source: >- Live probes of https://www.arc.gov/wp-json/ and https://services.arcgis.com/nkunl3y8FDxPkXDl/arcgis/rest/services on 2026-09-07, read against the standards each surface could plausibly implement. description: >- ARC makes no conformance claim anywhere on its site — there is no developer documentation to make one in. Every entry below was established by calling the API and reading what came back, and the negatives are as deliberate as the positives: for a federal-state commission publishing regional economic data, the standards a consumer would most expect (Project Open Data / DCAT and OGC API - Features) are the two that are absent. conformance: - id: rest name: HTTP REST over JSON conforms: true evidence: >- Both surfaces are resource-oriented HTTP APIs returning application/json. Verified across 100 derived operations on www.arc.gov/wp-json and four on the ArcGIS services host, 2026-09-07. - id: wordpress-rest-api name: WordPress REST API (wp/v2) conforms: true evidence: >- https://www.arc.gov/wp-json/ returns the core WordPress route-discovery document: 371 routes across 16 namespaces with full per-argument schemas, plus /wp/v2/types, /wp/v2/taxonomies and /wp/v2/statuses registries. Saved verbatim at openapi/_source/appalachian-regional-commission-wp-json-root.json. note: >- This is the closest thing ARC publishes to a machine-readable contract, and it is self-describing. - id: arcgis-rest-feature-service name: Esri ArcGIS REST API — Feature Service conforms: true evidence: >- https://services.arcgis.com/nkunl3y8FDxPkXDl/arcgis/rest/services?f=json returns currentVersion 12 and 108 FeatureServer entries; each service and layer returns the standard Esri descriptor and /query behaves per the Esri specification. Verified 2026-09-07. - id: geojson name: RFC 7946 GeoJSON conforms: true evidence: >- GET /services/arc_counties/FeatureServer/0/query?where=1%3D1&f=geojson returned an RFC 7946 FeatureCollection on 2026-09-07. Every ARC layer reports supportedQueryFormats "JSON, geoJSON, PBF". - id: rfc5988-web-linking name: RFC 5988 / RFC 8288 Web Linking conforms: true evidence: >- GET /wp-json/wp/v2/report?per_page=2&page=2 returned a Link header carrying rel="prev" and rel="next" on 2026-09-07. - id: pagination name: Documented pagination conforms: true evidence: >- page/per_page with X-WP-Total and X-WP-TotalPages on the WordPress surface; resultOffset/resultRecordCount with exceededTransferLimit on the ArcGIS surface. Both observed live. - id: cors name: Cross-origin resource sharing conforms: true evidence: >- The WordPress surface names X-WP-Total, X-WP-TotalPages and Link in access-control-expose-headers; the ArcGIS surface returns access-control-allow-origin "*". - id: rfc8414 name: RFC 8414 OAuth 2.0 Authorization Server Metadata conforms: partial evidence: >- https://arcgov.maps.arcgis.com/.well-known/oauth-authorization-server returned 200 with a valid RFC 8414 document (issuer, authorization_endpoint, token_endpoint, code_challenge_methods_supported S256) on 2026-09-07. Saved at well-known/appalachian-regional-commission-oauth-authorization-server.json. note: >- Marked partial deliberately. The document is served by Esri's platform for ARC's ArcGIS Online organization tenant, not authored or published by ARC, and ARC does not offer OAuth to third-party developers. arc.gov itself serves no /.well-known/ documents at all. - id: rfc9457 name: RFC 9457 Problem Details for HTTP APIs conforms: false evidence: >- Neither surface returns application/problem+json. WordPress returns {code, message, data.status}; ArcGIS returns {error:{code, message, details}} with HTTP 200. Observed live. - id: openapi name: Provider-published OpenAPI conforms: false evidence: >- /openapi.json, /openapi.yaml, /swagger.json and /api-docs all 404 on www.arc.gov, and data.arc.gov answers 403 behind a Cloudflare challenge. The six OpenAPI documents in this repository were derived by API Evangelist from the providers' own discovery documents and are stamped x-provider-published false. - id: openapi-derived name: Machine-readable contract available (derived) conforms: true evidence: >- openapi/ carries six OpenAPI 3.1.0 documents totalling 104 operations, every one derived from a live first-party discovery document (the WordPress route index and the ArcGIS services directory) fetched from an ARC-controlled host on 2026-09-07. - id: ogc-api-features name: OGC API - Features conforms: false evidence: >- /services/arc_counties/OGCFeatureServer and /OGCFeatureServer/conformance both returned the Esri error envelope {"error":{"code":400,"message":"Invalid URL"}}, and /WFSServer?service=WFS&request=GetCapabilities returned the generic services-directory HTML home page rather than a Capabilities document. ARC has not enabled OGC API - Features or WFS on any of its 108 services. Probed 2026-09-07. note: >- This is the one domain standard a regional geospatial data publisher would most be expected to meet, and it is a per-service toggle ARC could switch on. Consumers must speak Esri's REST dialect instead; f=geojson is the closest bridge. - id: project-open-data-dcat name: Project Open Data / DCAT-US public data inventory conforms: false evidence: >- https://www.arc.gov/data.json and https://www.arc.gov/digitalstrategy/data.json both returned 404 on 2026-09-07, and https://catalog.data.gov/api/3/action/organization_show?id=appalachian-regional-commission returned "Not Found". ARC publishes no /data.json enterprise data inventory. note: >- Recorded because ARC is a federal entity and this is the federal open-data convention. Not penalised as a market standard — it is noted as the specific, cheap, well-defined thing ARC could publish to make its 108 feature services and 304 reports discoverable as data. - id: asyncapi name: AsyncAPI / event surface conforms: false evidence: No webhook, streaming or event surface was found on any ARC host. Not applicable to a read-only data publisher. - id: security-txt name: RFC 9116 security.txt conforms: false evidence: /.well-known/security.txt returned 404 on www.arc.gov and arc.gov, and 302 to the 404 page on data.arc.gov. Probed 2026-09-07. domain_standard: market: government open data and regional geospatial statistics expected: - Project Open Data / DCAT-US (/data.json inventory) - OGC API - Features or WFS on the published geospatial services found: none detail: >- ARC's data is genuinely open and genuinely callable, but it speaks only vendor dialects — WordPress core's and Esri's. A consumer who already speaks DCAT or OGC API - Features still needs a bespoke connector for ARC. Both gaps are configuration, not engineering. maintainers: - FN: Kin Lane email: info@apievangelist.com