Stable by contract.
The public Nov Pax API uses explicit major versions and gives agents a predictable migration window before a supported version is retired.
Major paths, explicitly.
Stable operations live under a major URL path such as /api/v1.
Additive fields and clarifying documentation may ship within the current major version. A change that removes a field, changes its meaning or type, makes an optional input required, or otherwise breaks a conforming client requires a new major path.
Notice before retirement.
Nov Pax provides at least 90 days of public notice before retirement.
Once a version is deprecated, its responses include the RFC 9745 Deprecation header and a Link with rel="deprecation" pointing to migration guidance. A version is not marked deprecated before that lifecycle begins.
Removal gets a date.
When retirement is scheduled, responses also include the RFC 8594 Sunset header with the removal date. The deprecated version remains documented and operational through the announced window unless an urgent security or legal requirement makes continued operation unsafe.
One canonical record.
Current versions, operations, and schemas are published in the OpenAPI specification. The RFC 9727 API catalog links the API, documentation, health endpoint, and this policy from a standard machine-discovery location.