generated: '2026-08-13'
method: searched
source: >-
  https://developers.google.com/speed/docs/insights/v5/get-started,
  https://pagespeedonline.googleapis.com/$discovery/rest?version=v5 (revision 20260811),
  and live probes of https://www.googleapis.com/pagespeedonline/v5/runPagespeed on 2026-08-13
note: >-
  This API is a single read-only GET. Most cross-cutting conventions that exist for a
  CRUD API simply do not apply here, and they are recorded as explicit false/none rather
  than omitted — an absence a caller can rely on is worth as much as a presence.
authentication:
  style: api-key-query
  parameter: key
  header_alternative: null
  see: authentication/google-pagespeed-authentication.yml
idempotency:
  supported: false
  key_header: null
  note: >-
    There is no idempotency-key contract. The only operation is a GET, which is idempotent
    and safe by HTTP method, so a retry is free of side effects — but that is HTTP
    semantics, not a provider idempotency guarantee, and no Idempotency pointer is wired
    for it.
pagination:
  supported: false
  style: null
  note: One request analyses one URL and returns one result document. Nothing to page.
field_selection:
  supported: true
  parameter: fields
  style: google-partial-response
  description: >-
    Google's standard partial-response selector. `fields=lighthouseResult/categories/performance/score`
    trims the response to the requested subtree — materially useful here because a full
    PageSpeed response is very large.
  docs: https://developers.google.com/speed/docs/insights/v5/reference/pagespeedapi/runpagespeed
system_parameters:
  source: Discovery document global `parameters` block
  parameters:
    - {name: fields, description: Selector specifying which fields to include in a partial response}
    - {name: alt, description: Data format for the response}
    - {name: prettyPrint, description: Returns response with indentations and line breaks}
    - {name: quotaUser, description: Opaque per-user string for quota attribution when no user ID is available}
    - {name: callback, description: JSONP callback}
    - {name: key, description: API key}
    - {name: access_token, description: OAuth access token}
    - {name: oauth_token, description: OAuth 2.0 token for the current user}
    - {name: upload_protocol, description: Upload protocol for media}
    - {name: uploadType, description: Legacy upload protocol}
    - {name: "$.xgafv", description: V1 error format}
metadata:
  supported: false
  note: No user-supplied metadata is carried on requests or responses.
request_tracing:
  request_id_header: null
  note: >-
    No request-id or correlation header was observed on live responses. Response headers
    are minimal — vary, content-type, server: ESF, alt-svc. `quotaUser` is the only
    caller-supplied attribution handle, and it is a quota tag rather than a trace id.
versioning:
  style: uri-path
  current: v5
  contract_drift: discovery-revision + lighthouse-engine-version
  see: lifecycle/google-pagespeed-lifecycle.yml
error_envelope:
  format: google-rpc
  rfc9457: false
  content_type: application/json
  see: errors/google-pagespeed-problem-types.yml
rate_limit_signaling:
  headers: none
  observed_headers: []
  exhaustion_status: 429
  retry_after: false
  note: >-
    No X-RateLimit-*, RateLimit-* or Retry-After header is returned, on success or on
    exhaustion. An agent gets no runtime budget signal and must back off blind on 429.
  see: rate-limits/google-pagespeed-rate-limits.yml
long_running:
  async: false
  timeout_seconds: 120
  note: >-
    The call runs a real Lighthouse audit synchronously; Google's release notes record
    the maximum request timeout being raised to 120 seconds. Set client timeouts
    accordingly — this is the convention most integrations get wrong.
webhooks_events:
  supported: false
  note: No webhook, streaming or event surface exists.
write_surface:
  supported: false
  note: Read-only API. No POST/PUT/PATCH/DELETE operations exist.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com