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: Foreign Agricultural Service
providerId: foreign-agricultural-service
generated: '2026-09-10'
method: probed
source: >-
  live responses from https://apps.fas.usda.gov/OpenData/api/esr/regions on 2026-09-10, plus a
  read of the OpendataWeb portal and the Swagger 2.0 contract for any published limit
created: '2026-05-04'
modified: '2026-09-10'
tags:
  - Agriculture
  - Federal Government
  - Rate Limiting
description: >-
  Published rate limits for the USDA FAS Open Data Services: none. Recorded as a measured
  zero, with the probe that measured it.
supersedes: >-
  REPLACES the 2026-05-04 bulk-sweep scaffold, which asserted a three-tier ladder (10/100/1000
  requests per minute with 20/200/5000 burst), monthly quotas, X-RateLimit-Limit /
  X-RateLimit-Remaining / X-RateLimit-Reset / Retry-After / RateLimit-Policy response headers,
  429 and 503 status codes, and four rate-limit policies. NOT ONE of those was published by
  FAS or emitted by the API. The scaffold was written by the sweep, not harvested. Replaced
  with the probe result.
limit_count: 0
published: false
headers_observed: []
headers_note: >-
  Live responses carry only content-type, date, content-length,
  strict-transport-security and x-content-type-options. There is no RateLimit-*, no
  X-RateLimit-*, no Retry-After and no RateLimit-Policy. An agent has no runtime budget signal
  of any kind — it cannot see remaining quota and cannot distinguish throttling from the
  generic 500 this API returns on a bad credential.
status_on_exhaustion: null
status_note: 'no 429 is documented in the contract or mentioned on the portal; exhaustion behaviour is unknown'
limits: []
api_data_gov_note: >-
  A tempting wrong answer, recorded so the next pass does not make it. FAS mints its keys
  through the api.data.gov signup widget (the portal bundle loads
  api.data.gov/static/javascripts/signup_embed.js), and api.data.gov publishes a default
  hourly limit and X-RateLimit headers for the APIs it fronts. But api.data.gov does NOT proxy
  this API — apps.fas.usda.gov answers directly, its responses carry none of the gateway's
  headers, and its "Bad API Key" error body is FAS's own, not api.data.gov's. So the
  api.data.gov defaults are NOT this API's limits and are not recorded as such.
evidence:
  - request: GET https://apps.fas.usda.gov/OpenData/api/esr/regions (no API_KEY header)
    status: 403
    rate_limit_headers: none
    date: '2026-09-10'
  - request: 'GET https://apps.fas.usda.gov/OpenData/api/esr/regions with header API_KEY: <invalid>'
    status: 500
    rate_limit_headers: none
    date: '2026-09-10'
  - source: https://apps.fas.usda.gov/opendata/swagger/docs/v1
    finding: the contract documents exactly one response per operation (200 OK); no 429 and no limit is declared
  - source: https://apps.fas.usda.gov/opendataweb/home
    finding: the portal publishes no usage policy, quota or fair-use statement
unmeasured:
  note: >-
    The authenticated surface was not probed. API Evangelist holds no FAS API key and does not
    obtain credentials, so a limit that only reveals itself to a valid key — a per-key hourly
    ceiling enforced silently, for instance — would not appear here. limit_count: 0 means
    "nothing published and nothing signalled", not "proven unlimited".
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com