generated: '2026-09-05'
method: searched
provider: Cancer.gov
providerId: cancer-gov
source: The eight harvested first-party OpenAPI documents, the live GDC GraphQL schema, and NCI's own
  documentation (api.seer.cancer.gov/docs, api.seer.cancer.gov/terms, docs.gdc.cancer.gov, api-evsrest.nci.nih.gov).
summary:
  asserted: 13
  conforming: 8
  note: Cross-cutting web-API standards are largely absent; the domain-standard surface is unusually strong.
conformance:
- id: openapi
  conforms: true
  evidence: 'Eight first-party documents: OpenAPI 3.1.0 (SEER, https://api.seer.cancer.gov/v3/api-docs),
    3.0.1 (MoDaC https://modac.cancer.gov/v3/api-docs, EVS https://api-evsrest.nci.nih.gov/v3/api-docs)
    and 3.0.0 x5 on webapis.cancer.gov.'
- id: graphql
  conforms: true
  evidence: https://api.gdc.cancer.gov/v0/graphql answers an anonymous introspection query with HTTP 200;
    315 types, Root query type and a Mutation type. SDL in graphql/cancer-gov-gdc.graphql.
- id: oauth2
  conforms: false
  evidence: No securityScheme of type oauth2 in any of the eight specs, and no /.well-known/oauth-authorization-server
    on any host (all 404).
- id: oidc
  conforms: false
  evidence: No /.well-known/openid-configuration on any of the 11 hosts probed (all 404).
- id: rfc9457
  conforms: false
  evidence: No response in any spec declares application/problem+json. EVS returns a Spring-style RestException
    object {timestamp,status,error,message,path}; SEER returns its own Error object {type,table,columns,key,message}.
- id: json:api
  conforms: false
  evidence: No application/vnd.api+json media type anywhere in the specs.
- id: idempotency
  conforms: false
  evidence: No Idempotency-Key header is declared on any of the 96 mutating operations across the eight
    specs, and none is documented.
- id: pagination
  conforms: true
  evidence: 'Declared pagination parameters in the specs: SEER page/per_page/offset/from, EVS pageSize/limit/sort,
    glossary and drug-dictionary size/from, sitewide-search size/from, r4r size/from. Offset-based, no
    cursor, and the parameter names differ per service.'
- id: fhir
  conforms: false
  evidence: No FHIR resource types, no /metadata CapabilityStatement, and no application/fhir+json media
    type in any harvested contract.
- id: ga4gh-drs
  conforms: false
  evidence: Probed https://api.gdc.cancer.gov/ga4gh/drs/v1/service-info and /ga4gh/drs/v1/objects — both
    404. GDC exposes its own file/UUID download scheme instead.
- id: naaccr
  conforms: true
  category: domain-standard
  evidence: SEER*API exposes NAACCR — the North American Association of Central Cancer Registries data
    standard for cancer registries — as a first-class endpoint group. The spec at https://api.seer.cancer.gov/v3/api-docs
    carries a declared `naaccr` tag over the /rest/naaccr/* paths, and https://api.seer.cancer.gov/docs
    documents it as 'NAACCR Documentation'. A registry system that already speaks NAACCR consumes these
    item numbers and allowable values with no bespoke mapping.
- id: uicc-tnm-and-cs-staging
  conforms: true
  category: domain-standard
  evidence: 'SEER*API''s `staging` endpoint group implements the published cancer-staging algorithms themselves:
    the SEER documentation states TNM is based on the ''Union for International Cancer Control (UICC)
    TNM 7th edition'', Collaborative Stage is ''verified to match v02.05.50 C DLL'', EOD 2018 applies
    to cases diagnosed 2018 and later, and PDCS applies from 1 January 2024. The contract is the standard,
    not a description of it.'
- id: hcpcs
  conforms: true
  category: domain-standard
  evidence: SEER*API serves the CMS Healthcare Common Procedure Coding System through the declared `hcpcs`
    tag over /rest/hcpcs/* in https://api.seer.cancer.gov/v3/api-docs.
- id: ndc
  conforms: true
  category: domain-standard
  evidence: SEER*API serves the FDA National Drug Code Directory through the declared `ndc` tag over /rest/ndc/*
    in https://api.seer.cancer.gov/v3/api-docs.
- id: nci-thesaurus-ncit
  conforms: true
  category: domain-standard
  evidence: 'The EVS REST API is the reference implementation of NCI Thesaurus (NCIt) and NCI Metathesaurus,
    which are themselves the biomedical terminology standard for this sector. https://api-evsrest.nci.nih.gov/api/v1/metadata/terminologies
    returns the served terminologies with versions (ncit 26.06e, dated 2026-06-29); the spec declares
    Concept, Subset, Mapset, History, Metadata and Search endpoint groups over them. Terms of use: https://evs.nci.nih.gov/ftp1/NCI_Thesaurus/ThesaurusTermsofUse.htm.'
- id: sparql
  conforms: true
  category: domain-standard
  evidence: The EVS REST API exposes SPARQL over its terminologies — operationIds getSparqlBindings and
    searchSingleTerminologySparql in https://api-evsrest.nci.nih.gov/v3/api-docs — so an RDF client can
    query NCIt without an NCI-specific connector.