# v0 stability and upgrades

AgentsKit Chat follows SemVer as a fixed package group.

- Patch releases preserve public TypeScript signatures, protocol versions,
  component/event meaning, and persisted session compatibility.
- During `0.x`, a minor release may change a public contract, but only with an
  RFC or ADR as required, a changelog entry, a migration guide, and conformance
  evidence for all affected renderers.
- Protocol v1 payloads remain runtime validated. A breaking wire change uses a
  new protocol version and an explicit decoder/migration path.
- Deprecated APIs remain for at least one subsequent minor release unless a
  security issue makes that unsafe.
- AgentsKit peer minimums change only after upstream-first inspection and the
  full release matrix. No upstream implementation is copied downstream.

Applications should pin a minor line (`^0.4.0` for this release), commit their
lockfile, run renderer conformance and host E2E before upgrades, and review both
the changelog and migration guide. Stable `0.1.x` consumers should follow the
[0.2 migration](./migration-to-0.2.md). Alpha GitHub tarball consumers should
follow [the alpha migration](./migration-from-alpha.md). Stable `0.2.x`
consumers should follow the [0.3 package consolidation migration](./migration-to-0.3.md).
Applications already on `0.3.x` can adopt `0.4.0` without changing their
definition-owned sessions; controlled React and Ink modes are additive.