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: Zayo Group Holdings
providerId: zayo-group
generated: '2026-09-06'
method: searched
created: '2026-05-04'
modified: '2026-09-06'
source: >-
  Full read of https://developer.zayo.com/openapi/zayo.yaml (30 operations),
  https://developer.zayo.com/docs/getting-started and https://developer.zayo.com/docs/faq on
  2026-09-06.
tags:
- Fiber
- Network
- Telecom
- Rate Limiting
description: >-
  Zayo publishes no rate limits and emits no rate-limit signal. This is a measured zero, not an
  unchecked one: every one of the 30 operations in Zayo's own OpenAPI was examined and none
  declares a 429 response, a RateLimit-* or X-RateLimit-* header, or a Retry-After header, and
  the Getting Started page's error table stops at the 4xx/5xx range description without
  mentioning throttling. The practical consequence is that a client has no runtime budget
  signal at all — it cannot learn its remaining quota, and cannot be told when to come back.
limit_count: 0
limits: []
response_headers: []
responseCodes:
  throttled: null
  note: >-
    429 does not appear anywhere in the contract. Declared status codes across the whole
    surface are 200 (30 operations), 400 (29) and 401 (4), plus an undeclared
    components.responses.ServerError.
documented:
  in_contract: false
  in_docs: false
  contract_evidence: >-
    Zero occurrences of "429", "RateLimit", "X-RateLimit" or "Retry-After" in
    https://developer.zayo.com/openapi/zayo.yaml.
  docs_evidence: >-
    https://developer.zayo.com/docs/getting-started documents authentication, an API overview,
    versioning, error-handling ranges and support — and no limits.
    https://developer.zayo.com/docs/faq answers eleven questions, none about throttling.
observed:
  probed: false
  note: >-
    Not observed live. api.zayo.com requires OAuth client credentials issued by the Zayo API
    team on every path — an unauthenticated request returns 403 {"message":"Missing
    Authentication Token"} from AWS API Gateway — so there is no anonymous response on which to
    read runtime headers. API Evangelist holds no Zayo credentials and does not obtain them.
inferred_constraints:
- constraint: getCloudSites has no pagination
  detail: >-
    Zayo states "there is not pagination with this route", and the operation can return Zayo's
    entire cloud serviceability map when sent an empty request object. That is the largest
    single response on the surface and the most likely place an undocumented limit bites.
  source: https://developer.zayo.com/openapi/zayo.yaml
- constraint: validateBuildings caps at 20 buildings per request
  detail: >-
    The `buildings` array is minItems 1, maxItems 20, uniqueItems true. This is a payload
    bound, not a rate limit, but it is the only quantitative throttle Zayo publishes anywhere.
  source: https://developer.zayo.com/openapi/zayo.yaml
- constraint: default page size of 10
  detail: >-
    getservices and getNNIs default `paging.top` to 10 with no stated maximum, so a large
    inventory is many round trips.
  source: https://developer.zayo.com/openapi/zayo.yaml
policies:
- name: Client-side backoff
  description: >-
    With no server signal, clients should implement exponential backoff with jitter on 5xx and
    on any unexplained failure, and should not tune concurrency to a number Zayo has not
    published.
- name: Ask the account team
  description: >-
    Any operational limit is communicated through zayoapi@zayo.com or the Zayo account team,
    not through the API or the portal.
gap: >-
  Publishing RateLimit-Limit / RateLimit-Remaining / RateLimit-Reset (or the X-RateLimit-*
  family) and declaring a 429 with Retry-After would cost Zayo nothing in commercial terms —
  the API is free — and would turn an unknowable budget into a runtime-readable one.
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com