generated: '2026-08-02'
method: searched
source: https://developer.401go.com/docs/versioning
api: 401GO API

versioning:
  scheme: header-date
  header: api-version
  format: ISO date string (YYYY-MM-DD)
  granularity: per-endpoint
  current: null
  current_note: >-
    401GO publishes no version list or "current version" marker. Versions are addressed by
    date, and the effective default is the version current on the date the calling application
    was registered. The OpenAPI info.version is 1.0.0 but is not the addressable API version.
  default_behavior: >-
    Omitting the header pins the client to the version that was current when its application
    was registered, so existing integrations retain backwards compatibility indefinitely.
  resolution: >-
    If the supplied date falls between two published versions, the API serves the latest
    version older than or equal to the supplied date.
  guidance: 401GO recommends always building to the latest version of each endpoint.
  docs: https://developer.401go.com/docs/versioning

deprecation:
  policy_url: null
  policy_published: false
  sunset_header: false
  deprecation_header: false
  note: >-
    No deprecation or sunset policy is published, and no RFC 8594 Sunset/Deprecation header
    support is documented. The date-pinned versioning scheme is the de facto compatibility
    guarantee — old endpoint versions are retained rather than deprecated — but no retirement
    window, notice period, or sunset signal is stated anywhere in the developer docs.

deprecated_operations: []
deprecated_operations_note: >-
  Zero of the 72 operations in the published OpenAPI carry deprecated: true.

status_page:
  url: null
  published: false
  probed:
  - {url: 'https://status.401go.com', result: NXDOMAIN}
  - {url: 'https://401go.statuspage.io', result: 200 but resolves to the Statuspage marketing site, not a 401GO status page}
  - {url: 'https://401go.instatus.com', result: 200 but a generic Instatus shell, not a 401GO status page}
  note: >-
    No status page or uptime dashboard was found on any 401GO host or on the common hosted
    status providers. Incident communication appears to run through the assigned partner
    developer contact.

sla:
  url: null
  uptime_target: null
  note: >-
    No public SLA or uptime commitment is published on the developer portal or the marketing
    site. Terms are at https://401go.com/terms-and-conditions/.

changelog:
  url: null
  published: false
  note: >-
    The ReadMe-hosted developer portal exposes no /changelog. Individual doc pages carry an
    updatedAt timestamp in their markdown frontmatter, which is the only change signal
    available. Most recent observed updates - payroll-integration 2026-05-06,
    getting-started 2026-06-25, api-endpoint-and-method-access 2026-04-20,
    authentication 2026-04-22, versioning 2025-08-15, api-errors 2025-06-23.

release_process:
  documented: true
  stages:
  - {stage: 1, name: Contact, detail: 'Scopes, timelines and requirements defined with 401GO; a developer contact is assigned; mutual beta clients identified.'}
  - {stage: 2, name: Sandbox, detail: Partner receives sandbox access and builds against it.}
  - {stage: 3, name: Verification & Testing, detail: 401GO verifies functionality and compliance with its standards.}
  - {stage: 4, name: Beta, detail: Production credentials issued; integration runs with a select group of clients.}
  - {stage: 5, name: Full Release, detail: Integration made available to all interested users.}
  source: https://developer.401go.com/docs/getting-started

gaps:
- No public status page.
- No published deprecation or sunset policy.
- No changelog.
- No SLA or uptime target.
- No published list of available api-version dates, so a client cannot discover which versions exist.