API Evangelist enhancements — Bonneville Power Administration Transmission API

overlay: 1.0.0
info:
  title: API Evangelist enhancements — Bonneville Power Administration Transmission API
  version: 1.0.0
  x-generated: '2026-09-06'
  x-method: derived
  x-source: live probes of the BPA ArcGIS REST endpoints described by the extended document, 2026-09-06
extends: openapi/bonneville-power-administration-transmission-api-openapi.yml
actions:
- target: $.info
  description: Record how the response format is actually negotiated on this API.
  update:
    x-content-negotiation:
      mechanism: query-parameter
      parameter: f
      values:
      - json
      - geojson
      - pjson
      - html
      note: 'The Accept header is ignored. An agent that sets Accept: application/geo+json and omits f=geojson
        receives ArcGIS JSON.'
- target: $.info
  description: Record that errors are returned inside HTTP 200, which the responses object cannot express.
  update:
    x-error-envelope:
      format: esri-error
      shape: '{"error": {"code": <int>, "message": <string>, "details": [<string>]}}'
      http_status_is_authoritative: false
      agent_rule: Treat a response as failed when the parsed body carries a top-level `error` key, regardless
        of HTTP status.
      catalog: errors/bonneville-power-administration-problem-types.yml
      evidence: GET .../BPA_ServiceArea/FeatureServer/0/query?where=BADSQL&f=json returned HTTP 200 with
        an error envelope, probed 2026-09-06.
- target: $.info
  description: Record the observed runtime rate-limit and cache signalling.
  update:
    x-runtime-signals:
      rate_limit_headers:
      - x-esri-org-request-units-per-min
      - x-esri-query-request-units
      rate_limit_model: Esri request units per minute, budgeted across the whole BPA tenant, not per caller.
      cache_control: public, max-age=30, s-maxage=30
      conditional_get: ETag returned on every layer response.
      cors:
        access-control-allow-origin: '*'
      observed: '2026-09-06'
- target: $.info
  description: Record the read-only posture explicitly so agent tooling does not look for write guards.
  update:
    x-agent-semantics:
      read_only: true
      idempotency: na
      reversibility: na
      dry_run: na
      rationale: Every operation is a GET query against a published dataset. There is no mutating operation,
        so replay protection and reversal windows do not apply.
      conventions: conventions/bonneville-power-administration-conventions.yml
- target: $.paths['/services/BPA_TransmissionLines_View/FeatureServer/0/query'].get.parameters
  description: Add the paging and projection parameters the layer supports but the spec omits (confirmed
    against the live layer definition, advancedQueryCapabilities.supportsPagination true).
  update: &id001
  - name: resultOffset
    in: query
    description: Zero-based index of the first feature to return. Pairs with resultRecordCount for paging.
    schema:
      type: integer
      minimum: 0
  - name: resultRecordCount
    in: query
    description: Maximum features to return; capped by the layer maxRecordCount. When more match, the
      response sets exceededTransferLimit true.
    schema:
      type: integer
      minimum: 1
  - name: returnGeometry
    in: query
    description: Set false to return attributes only and omit the geometry.
    schema:
      type: boolean
      default: true
  - name: returnCountOnly
    in: query
    description: Set true to return only the count of matching features.
    schema:
      type: boolean
      default: false
- target: $.paths['/services/BPA_TransmissionStructure_View/FeatureServer/0/query'].get.parameters
  description: Add the paging and projection parameters the layer supports but the spec omits (confirmed
    against the live layer definition, advancedQueryCapabilities.supportsPagination true).
  update: *id001