generated: '2026-08-28'
method: derived
source: llms/group-1-automotive-llms.txt (provider-published) plus live observation of https://www.group1auto.com/llm/inventory/
  on 2026-08-28.
scope: 'Cross-cutting semantics for the only machine-callable surface Group 1 Automotive publishes:
  the anonymous /llm/inventory/ browse endpoint advertised in its own llms.txt. Group 1 does not publish
  an API style guide, so everything below is derived from the documented parameter set and from what
  the endpoint actually returned — nothing is asserted that was not observed or stated in llms.txt.'
authentication:
  style: none
  detail: No API key, token, cookie or signed request. The endpoint is anonymous and public. The provider
    publishes no authentication documentation because there is nothing to authenticate.
  source: https://www.group1auto.com/llms.txt
transport:
  protocol: HTTPS
  tls_version: TLSv1.3
  methods:
  - GET
  content_type: text/html; charset=UTF-8
  content_negotiation:
    supported: false
    detail: No JSON representation is offered. A format=json query parameter is ignored and the response
      remains HTML; /llm/inventory.json returns the site's 404 page. An agent must parse the server-rendered
      markup.
pagination:
  style: page-number with explicit size
  params:
  - name: page
    role: 1-indexed page number
  - name: limit
    role: records per page
  response_signals:
  - The rendered page states its own position and total, e.g. "Page 1 of 13044 (26088 total vehicles)"
    — a total count and a page count are both exposed to the reader.
  cursor: false
  link_headers: false
  source: llms.txt "Parameters" line; totals observed in the rendered response 2026-08-28.
filtering:
  style: flat query-string predicates, AND-combined
  params:
  - name: type
    kind: enum
    values:
    - new
    - used
  - name: make
    kind: string
  - name: model
    kind: string
  - name: year_min
    kind: integer
    kind_detail: inclusive lower bound
  - name: year_max
    kind: integer
    kind_detail: inclusive upper bound
  - name: price_min
    kind: integer
    kind_detail: USD
    inclusive lower bound: null
  - name: price_max
    kind: integer
    kind_detail: USD
    inclusive upper bound: null
  - name: bodytype
    kind: enum
    values:
    - SUVs
    - Trucks
    - Vans
    - Sedans
  - name: keyword
    kind: string
    kind_detail: free-text match
    e.g. a color: null
  ranges_use_min_max_suffixes: true
  note: Range filters follow a consistent _min/_max suffix convention across year and price. That consistency
    is the closest thing to a published design convention in the surface.
field_expansion:
  supported: false
sparse_fieldsets:
  supported: false
metadata:
  supported: false
request_tracing:
  request_id_header: null
  detail: No X-Request-Id or correlation header is returned. Responses do carry an x-cars-signature-v1
    header and an x-envoy-upstream-service-time value, both artifacts of the Cars.com / Dealer Inspire
    hosting platform rather than a documented tracing contract.
versioning:
  scheme: none
  detail: The path carries no version segment and no version header is sent. There is no published deprecation
    policy, no changelog, and no stated stability guarantee for /llm/inventory/ or for the parameter
    names in llms.txt. An agent has no signal if the shape changes.
error_envelope:
  format: HTML
  detail: Errors are the site's ordinary HTML error pages, not a structured envelope. There is no RFC
    9457 application/problem+json. A 404 returns a full 552KB Dealer Inspire marketing 404 page; a bot-management
    refusal returns a 4,569-byte Cloudflare "Attention Required!" interstitial with status 403. Neither
    is machine-classifiable beyond the status code.
  rfc9457: false
rate_limit_signaling:
  response_headers: []
  detail: 'No RateLimit-*, X-RateLimit-* or Retry-After headers were observed on a 200 response. The
    only published throughput signal is "Crawl-delay: 1" in robots.txt. See rate-limits/group-1-automotive-rate-limits.yml.'
idempotency:
  supported: na
  detail: Not applicable. The surface is read-only — GET only, no write operations exist — so there
    is nothing to double-fire and no idempotency key to carry.
dry_run_mode:
  supported: na
  detail: Not applicable. Read-only surface; there is no action to rehearse.
reversibility:
  grade: na
  applicable: false
  write_surface: false
  detail: 'Group 1 Automotive publishes no write operation on any machine-readable surface. The only
    documented endpoint, GET /llm/inventory/, retrieves vehicle inventory and changes no state, so there
    is no action for an agent to take back. reversibility, dry_run_mode and idempotency are all `na`
    here for the same reason, and na is the honest answer rather than a zero: a read-only API cannot
    fail a reversal test it can never be asked to take. Note that the consumer-facing purchase, financing,
    trade-in and service-scheduling flows on AcceleRide are human web forms, not documented API operations,
    and are therefore out of scope for this artifact — no reversal window is asserted for them here
    because the provider states none in any machine-readable form.'
  reversal_operations: []
cross_links:
  agentic_access: agentic-access/group-1-automotive-agentic-access.yml
  rate_limits: rate-limits/group-1-automotive-rate-limits.yml
  plans: plans/group-1-automotive-plans-pricing.yml
  llms_txt: llms/group-1-automotive-llms.txt
  errors: null
  lifecycle: null
  authentication: null