overlay: 1.0.0
info:
title: API Evangelist enhancements for ClinicalTrials.gov studies-api
version: 1.0.0
extends: openapi/clinical-trials-gov-studies-api-openapi.yml
x-provenance:
generated: '2026-09-06'
method: generated
source: >-
API Evangelist enrichment pass. Every value applied here was read from a live probe of
https://clinicaltrials.gov/api/v2 or from the provider's own documentation on
2026-09-06 — nothing is asserted that was not observed. The underlying OpenAPI is not
mutated.
actions:
- target: $.info
update:
x-apievangelist-slug: clinical-trials-gov
x-api-lifecycle: production
x-api-version-live: 2.0.5
x-data-refresh-cadence: daily
x-authentication: none
x-license: U.S. Government public domain (see https://clinicaltrials.gov/about-site/terms-conditions)
x-agent-readiness:
write_surface: false
idempotency: na
reversibility: na
rate_limit_headers: none
- target: $.info.contact
update:
name: NLM Support
url: https://support.nlm.nih.gov/
- target: $
update:
x-conventions: conventions/clinical-trials-gov-conventions.yml
x-error-catalog: errors/clinical-trials-gov-problem-types.yml
x-lifecycle: lifecycle/clinical-trials-gov-lifecycle.yml
x-authentication-profile: authentication/clinical-trials-gov-authentication.yml
x-rate-limits: rate-limits/clinical-trials-gov-rate-limits.yml
x-data-model: data-model/clinical-trials-gov-data-model.yml
x-conformance: conformance/clinical-trials-gov-conformance.yml
- target: $.paths['/studies/{nctId}'].get
update:
x-response-formats:
- json
- csv
- fhir.json
x-fhir:
profile: http://hl7.org/fhir/uv/ebm/StructureDefinition/study-registry-record
media_type: application/fhir+json
docs: https://clinicaltrials.gov/data-api/fhir
status: pilot
evidence: 'GET /api/v2/studies/NCT00141635?format=fhir.json -> 200 application/fhir+json (probed 2026-09-06)'
x-alias-redirect: 'since API 2.0.2, resolves NCTIdAlias values to the current record'
- target: $.paths['/studies'].get
update:
x-query-language: Essie expression syntax
x-query-docs: https://clinicaltrials.gov/find-studies/constructing-complex-search-queries
x-pagination:
style: opaque-cursor
request: [pageSize, pageToken, countTotal]
response: [nextPageToken, totalCount]
x-undocumented-parameters:
- name: aggFilters
note: >-
Documented only in the 2026-01-22 release note (the 'ressub' Results Submitted
filter); absent from the description document.
- target: $.paths['/studies/metadata'].get
update:
x-role: >-
Authoritative machine-readable field dictionary for the whole study record; the real
data model lives here rather than in components.schemas.
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