API Evangelist enhancements for the ITU DataHub API

overlay: 1.0.0
info:
  title: API Evangelist enhancements for the ITU DataHub API
  version: 1.0.0
extends: openapi/itu-datahub-openapi.yml
x-apievangelist-note: >-
  ITU publishes no OpenAPI, so the document this overlay extends was itself derived by API
  Evangelist from live observed responses. This overlay carries the annotations that describe the
  API's real-world operating conditions — provenance, the absence of a lifecycle contract, and the
  identifier and payload traps a consumer will hit — separately from the description of the surface
  itself.
actions:
- target: $.info
  update:
    x-apievangelist-provenance: derived from live anonymous probes, 2026-07-26
    x-apievangelist-stability: unstable-by-omission
    x-apievangelist-support: none published
    x-apievangelist-terms: no terms of programmatic use published
- target: $.info
  update:
    x-apievangelist-artifacts:
      authentication: authentication/itu-authentication.yml
      conventions: conventions/itu-conventions.yml
      errors: errors/itu-problem-types.yml
      lifecycle: lifecycle/itu-lifecycle.yml
      conformance: conformance/itu-conformance.yml
      data_model: data-model/itu-data-model.yml
      mcp: mcp/itu-mcp.yml
      skills: skills/_index.yml
- target: $.servers[0]
  update:
    x-apievangelist-rate-limits: none published; no rate-limit headers returned. Self-throttle.
    x-apievangelist-cors: 'access-control-allow-origin: * — callable directly from a browser.'
- target: $.paths['/data/bycode/{codeID}'].get
  update:
    x-apievangelist-payload-warning: >-
      Returns the full cross-country series in one unpaginated array — roughly 1.1 MB for codeID
      11624. Prefer getDataByCodeAndIso where a single country is needed.
- target: $.paths['/idi/data/bycountryid/{countryID}'].get
  update:
    x-apievangelist-identity-warning: >-
      Keys on the numeric ITU CountryID from listCountries, NOT the ISO 3166-1 code. Supplying an
      ISO code or an unknown id returns HTTP 200 with an empty array rather than an error.
- target: $.paths['/umc/bycountryid/{countryID}'].get
  update:
    x-apievangelist-identity-warning: >-
      Keys on the numeric ITU CountryID from listCountries, NOT the ISO 3166-1 code.
- target: $.paths['/dictionaries/getbyid/{codeID}'].get
  update:
    x-apievangelist-error-warning: >-
      An unknown codeID returns HTTP 500 with a raw JavaScript TypeError string in the body. Treat
      it as "no such indicator", and resolve codeIDs from getIndicatorCategories first.
- target: $.components.schemas.DataPoint
  update:
    x-apievangelist-type-warning: >-
      answer[].value is a STRING on this schema but a NUMBER on AggregatePoint. Parse defensively.
- target: $.components.schemas.Country
  update:
    x-apievangelist-naming-warning: >-
      This is the only endpoint using PascalCase field names (CountryID, IsoCode, ShortName). Every
      other DataHub response uses camelCase.