generated: '2026-08-13'
method: probed
source: live unauthenticated responses from https://api.cello.so plus a full read of https://docs.cello.so
limit_count: 0
summary: >-
  Cello publishes no rate limits. Every page in the docs index (86 pages, read via
  https://docs.cello.so/llms.txt) was searched for limits, throttling, quotas and 429s and none
  document a request ceiling, a window, a burst allowance, or a per-key/per-account policy. The
  pricing page meters referral ARR and partner counts, not API calls, and attaches no request
  quota to any tier. Live unauthenticated responses from api.cello.so return no rate-limit headers
  of any family — no X-RateLimit-*, no RateLimit-*, no Retry-After. An integrator cannot tell from
  the docs or from the runtime what the ceiling is, or whether one exists.
documented_limits: []
response_headers:
  observed: []
  x_ratelimit_family: false
  ratelimit_draft_family: false
  retry_after: false
  note: >-
    Headers observed on a live 401 from GET https://api.cello.so/referral-codes/{code}: date,
    content-type, content-length, www-authenticate, apigw-requestid. On a live 401 from
    POST https://api.cello.so/token: the Helmet security-header set (CSP, HSTS, X-Frame-Options,
    X-Content-Type-Options, Referrer-Policy, COOP/CORP), etag, vary, and apigw-requestid. No
    rate-limit signaling in either.
exhaustion:
  status_code: null
  body: null
  note: Not observed; no limit was reached and no limit is documented.
infrastructure:
  gateway: AWS API Gateway
  evidence: >-
    Every api.cello.so response carries an apigw-requestid header, the AWS API Gateway request
    identifier. API Gateway supports usage plans with throttle and quota settings, so a limit may
    well be enforced at the edge — but nothing in the response surface or the docs tells a client
    what it is.
  note: >-
    apigw-requestid is the only correlation identifier Cello returns; it is not documented as a
    support handle anywhere in the docs.
x-evidence:
  fetched: '2026-08-13'
  probes:
  - {url: 'https://api.cello.so/referral-codes/TESTCODE123', http_status: 401, note: 'no rate-limit headers'}
  - {url: 'https://api.cello.so/token', http_status: 401, note: 'POST with invalid credentials; no rate-limit headers'}
  - {url: 'https://docs.cello.so/llms.txt', http_status: 200, note: '86 documented pages; none is a limits/quotas page'}
  - {url: 'https://docs.cello.so/api-reference/introduction.md', http_status: 200, note: 'base URLs and auth only, no limits section'}
  - {url: 'https://cello.so/pricing/', http_status: 200, note: 'no API-call quota or overage on any tier'}