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: Australian National University
providerId: anu
created: '2026-06-03'
modified: '2026-08-19'
reconciled: false
tags:
- Education
- Higher Education
- University
- Rate Limiting
description: >-
  ANU publishes no unified rate-limit table across its APIs, but one hard, published limit
  does exist and was confirmed by live probe on 2026-08-19: the deprecated QRNG@ANU legacy
  endpoint is throttled to ONE request per minute. Critically, it does NOT signal that with
  429 — it returns HTTP 200 with a plain-text sentence in place of the JSON envelope, and
  emits no Retry-After header. A client that branches on status code will ingest the refusal
  as data. The current AQN service meters per API key through an AWS API Gateway usage plan
  whose numbers ANU does not publish. OAI-PMH harvesting is unmetered but should be polite.
notes: >-
  method: probed. The 429 assumption in the previous version of this file was wrong for the
  legacy endpoint and is corrected below.
sources:
- https://qrng.anu.edu.au/contact/api-documentation/
- https://qrng.anu.edu.au/API/jsonI.php?length=4&type=uint8
- https://quantumnumbers.anu.edu.au/documentation
responseCodes:
  throttled: 200
  throttled_note: >-
    The legacy QRNG endpoint returns 200 text/html on throttle, not 429. The AQN gateway is
    documented to use 429 for quota exhaustion but this was not observed without a key.
limits:
- name: QRNG@ANU legacy JSON API
  surface: https://qrng.anu.edu.au/API/jsonI.php
  scope: client
  metric: requests-per-minute
  limit: 1
  enforcement: HTTP 200 with a plain-text refusal body; no Retry-After, no 429.
  source: https://qrng.anu.edu.au/contact/api-documentation/
  verified: '2026-08-19'
- name: ANU Quantum Numbers (AQN) API
  surface: https://api.quantumnumbers.anu.edu.au
  scope: api-key
  metric: requests-per-key
  limit: unpublished
  enforcement: AWS API Gateway usage plan; 429 expected on quota exhaustion.
  notes: Quota values are not published. A free key is issued self-serve.
- name: ANU Open Research OAI-PMH
  surface: https://openresearch-repository.anu.edu.au/server/oai/request
  scope: client
  metric: none-published
  limit: unpublished
  notes: No documented limit. Use resumptionToken paging and harvest off-peak.
policies:
- name: Backoff Strategy
  description: Exponential backoff with jitter; honor Retry-After; harvest during off-peak hours.
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com