specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: Alcohol and Tobacco Tax and Trade Bureau
providerId: alcohol-and-tobacco-tax-and-trade-bureau
generated: '2026-09-01'
method: searched
source: >-
  https://www.ttb.gov/data ; live unauthenticated responses from
  https://www.ttb.gov/images/foia/cola_stats.xml and
  https://www.ttb.gov/system/files/2024-08/Tobacco_Products_Data.json, probed 2026-09-01
created: '2026-05-04'
modified: '2026-09-01'
limit_count: 0
tags:
  - Alcohol
  - Tobacco
  - Federal Government
  - Excise Tax
  - Open Data
  - Rate Limiting
description: >-
  TTB publishes no rate limits, and its responses carry no rate-limit signalling. This file
  REPLACES a 2026-05-04 bulk-sweep scaffold that asserted free/professional/enterprise tiers at
  10/100/1000 requests per minute with X-RateLimit-* headers and a 429 on exhaustion. None of
  that was ever true of TTB: there are no tiers, no API keys, no quota, and no rate-limit
  headers on any observed response. The real constraint on a consumer is not a quota but the
  shape of the surface — the data is served as whole static files behind an Akamai cache, so
  polling more often than the daily refresh returns identical bytes.
headers: {}
observed_response_headers:
  probed: '2026-09-01'
  url: https://www.ttb.gov/images/foia/cola_stats.xml
  rate_limit_headers_present: false
  retry_after_present: false
  note: >-
    No RateLimit-*, X-RateLimit-* or Retry-After header on any 200 response from www.ttb.gov.
responseCodes:
  throttled: null
  quotaExceeded: null
  serviceUnavailable: null
limits: []
policies:
  - name: No published limits
    description: >-
      TTB documents no request quota, burst ceiling or throttling policy for its open data. The
      files are served anonymously from an Akamai-fronted origin with no credential to meter
      against.
  - name: Refresh cadence is the real ceiling
    description: >-
      The daily feeds (cola_stats.xml, form_stats.csv) declare accrualPeriodicity R/P1D in the
      Treasury DCAT-US catalog and carry a creation_date field in the payload itself. Polling
      more than once a day yields unchanged content; use the embedded creation_date to detect a
      new vintage rather than re-downloading on a short interval.
  - name: Acceptable-use is governed by policy, not by a limiter
    description: >-
      Automated access is governed by the TTB privacy policy and legal notice and by the
      www.ttb.gov robots.txt (HTTP 200, 2,027 bytes), not by an enforced technical limit.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com