The API has a major version in the path (/v1) and dated versions within it. The current version is
2026-11-01.
- Each key is pinned to the dated version that was current when it was created. Your integration keeps getting the same behaviour until you choose to upgrade.
- To try another version for one request, send
Fleet-Version: 2026-11-01. Responses always include theFleet-Versionthey were served with. - An unknown version is refused with
400 unsupported_version.
What we change without a new version
Section titled “What we change without a new version”These are backwards-compatible, and your code should tolerate them:
- New endpoints, and new optional request parameters.
- New fields in responses, and new values in
objecttypes. - New error codes (handle unknown codes by their HTTP status).
- New values in enums documented as open (for example
sourceon meter entries).
What needs a new version
Section titled “What needs a new version”Removing or renaming a field, changing a type or format, making an optional parameter required, or changing
default behaviour. Old versions keep working for at least 12 months after a new one ships, and responses from a
deprecated version will carry Deprecation and Sunset headers. Every change is in the changelog.