Compatibility
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What counts as a breaking change, how versions protect you and the change classes the changelog uses.
Within a version, Kelly makes only changes that don't break a client built to these docs; anything else ships as a new dated version.
What doesn't break youLink to this section
- New operations, topics, fields, enum values, error codes and headers. Ignore what you don't know: every enum is open, and Wire clients ignore unknown
opandtypevalues and unknown members. - Rewording
detail, descriptions and other prose.
What wouldLink to this section
Removing or renaming a field, operation or code, changing a field's type or meaning, making an optional input required, or narrowing the values an input accepts. These ship only in a new version, sent as Api-Version. The versions served today are 2026-10-05.
Change classesLink to this section
Every changelog line carries one class: Additive, Contract (can break a client), Agent behaviour (changes what an AI client's model reads), Operational or Commercial (prices, limits, access).
NoticeLink to this section
No version has been retired yet, so no notice period has been used. How a version is retired is on the deprecation page.