generated: '2026-06-20'
method: derived
source: openapi/*.yml + https://api.nasa.gov/ + https://api.data.gov/docs/rate-limits/
notes: >-
  Cross-cutting request/response semantics for the NASA Open APIs, derived from
  the captured OpenAPI and the api.data.gov gateway docs.
authentication:
  style: api-key
  location: query
  parameter: api_key
  see: authentication/nasa-authentication.yml
idempotency:
  supported: false
  reason: All operations are safe GET requests; no write endpoints, no idempotency keys.
pagination:
  styles:
    - api: NeoWs
      style: page-number
      params: [page, size]
      response_fields: [links, page, element_count]
    - api: Image and Video Library
      style: page-number
      params: [page]
      response_fields: [collection.links, collection.metadata.total_hits]
    - api: EPIC / DONKI / APOD / Mars Photos
      style: none
      notes: Bounded by date, sol, or count parameters rather than cursor/page paging.
field_expansion:
  supported: false
metadata:
  supported: partial
  notes: Image and Video Library responses wrap results in a collection object with metadata.total_hits and links.
request_tracing:
  request_id_header: null
versioning:
  style: uri-path
  see: lifecycle/nasa-lifecycle.yml
error_envelope:
  format: plain-json
  shape: '{ "error": { "code": "...", "message": "..." } }'
  see: errors/nasa-problem-types.yml
rate_limit_signaling:
  headers: [X-RateLimit-Limit, X-RateLimit-Remaining]
  exceeded_status: 429
  see: rate-limits/nasa-rate-limits.yml