generated: '2026-09-12'
method: searched
source: https://api.data.gov/docs/developer-manual/ (the shared key model for every api.gsa.gov / api.data.gov
  surface) and the per-API auth sections on open.gsa.gov, reconciled against the securitySchemes in openapi/general-services-administration-analytics-dap-openapi.yaml,
  openapi/general-services-administration-apidatagov-admin-openapi.yaml, openapi/general-services-administration-apidatagov-metrics-openapi.yaml,
  openapi/general-services-administration-per-diem-openapi.yaml, openapi/general-services-administration-regulations-gov-openapi.yaml,
  openapi/general-services-administration-sam-subcontracting-plan-reports-openapi.yaml, openapi/general-services-administration-searchgov-clicks-openapi.yaml,
  openapi/general-services-administration-touchpoints-openapi.yaml
summary:
  types:
  - apiKey
  - http
  api_key_in:
  - header
  - query
schemes:
- name: ApiKeyAuth
  type: apiKey
  in: header
  parameter: X-API-KEY
  sources:
  - openapi/general-services-administration-analytics-dap-openapi.yaml
  - openapi/general-services-administration-per-diem-openapi.yaml
  - openapi/general-services-administration-searchgov-clicks-openapi.yaml
- name: api_key
  type: apiKey
  in: header
  parameter: X-Api-Key
  sources:
  - openapi/general-services-administration-apidatagov-admin-openapi.yaml
  - openapi/general-services-administration-apidatagov-metrics-openapi.yaml
  - openapi/general-services-administration-regulations-gov-openapi.yaml
- name: admin_auth_token
  type: apiKey
  in: header
  parameter: X-Admin-Auth-Token
  sources:
  - openapi/general-services-administration-apidatagov-admin-openapi.yaml
- name: ApiKeyQueryAuth
  type: apiKey
  in: query
  parameter: api_key
  sources:
  - openapi/general-services-administration-apidatagov-metrics-openapi.yaml
- name: basicAuth
  type: http
  scheme: basic
  description: System Account name and password provided via HTTP Basic authentication.
  sources:
  - openapi/general-services-administration-sam-subcontracting-plan-reports-openapi.yaml
- name: api_key
  type: apiKey
  in: header
  parameter: x-api-key
  sources:
  - openapi/general-services-administration-touchpoints-openapi.yaml
docs:
- https://api.data.gov/docs/developer-manual/
- https://api.data.gov/signup/
- https://open.gsa.gov/api/entity-api/
- https://open.gsa.gov/api/get-opportunities-public-api/
model:
  shared_key_service: api.data.gov (API Umbrella), operated by GSA Technology Transformation Services
  description: 'Almost every GSA API is fronted by api.data.gov. One 40-character api.data.gov key works
    across every participating agency API, GSA''s included. SAM.gov is the exception: its keys are issued
    from the SAM.gov Account Details page (alpha.sam.gov for the prodlike environment), and its sensitive/FOUO
    endpoints additionally require a System Account username+password over HTTP Basic.'
  key_delivery:
  - style: header
    parameter: X-Api-Key
    example: 'curl -H ''X-Api-Key: DEMO_KEY'' https://api.gsa.gov/travel/perdiem/v2/rates/conus/lodging/2025'
  - style: query
    parameter: api_key
    example: https://api.gsa.gov/technology/site-scanning/v1/websites?api_key=DEMO_KEY
  - style: basic-username
    parameter: api key as username, empty password
    example: curl https://YOUR_KEY@api.gsa.gov/...
  signup: https://api.data.gov/signup/
  anonymous_exploration_key:
    value: DEMO_KEY
    limits: 30 requests per IP per hour, 50 per IP per day
  sam_gov_system_accounts:
    applies_to:
    - SAM.gov Entity Management (FOUO / Sensitive)
    - SAM.gov Federal Hierarchy FOUO
    - SAM.gov Subcontracting Plan Reports
    - SAM.gov Extracts (CUI)
    mechanism: System Account User ID and password sent as HTTP Basic under Authorization, base64(username:password);
      the API key must travel in the x-api-key HEADER and not in the request URL; Accept and Content-Type
      must both be application/json.
    docs: https://open.gsa.gov/api/entity-api/
  oauth2: false
  oidc: false
  mtls: false
findings:
- Six distinct securityScheme names describe ONE mechanism. ApiKeyAuth, api_key, ApiKeyQueryAuth and the
  Touchpoints api_key are all the same api.data.gov key, spelled X-API-KEY, X-Api-Key, x-api-key and ?api_key=
  across four specs. An agent reading the contracts alone cannot tell that one credential serves all of
  them.
- 14 of the 22 harvested OpenAPIs declare NO securitySchemes at all, including every SAM.gov entity, exclusions,
  contract-award and subaward spec, even though every one of those endpoints rejects an unkeyed request.
  Authentication is documented in prose on open.gsa.gov and omitted from the contract.
- No OAuth 2.0, OpenID Connect or mutual TLS anywhere in the GSA public API estate; scopes/ is therefore
  not applicable.