> For the complete documentation index, see [llms.txt](https://sdk.metamarket.tech/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sdk.metamarket.tech/releases-and-reference/deprecation-policy.md).

# Deprecation Policy

How a change that could break an existing integration is handled. The aim is to give partners advance notice and migration guidance rather than spring a breaking change on them.

Because integrations are onboarded and run with the team, notice of a breaking change reaches partners directly through that channel, with the migration guidance needed to move across. A change is treated as breaking when it alters an existing route, payload field, error contract, authentication behaviour, or configuration contract in a way an existing client depends on. Additive change, a new optional field or a new channel, is not breaking and does not require migration; that is the intended posture for the response envelope.

Where a change is unavoidable, the previous behaviour is kept working alongside the new one through a migration window, and the deprecated behaviour and its replacement are called out in the [Release notes](/releases-and-reference/release-notes.md) and [Compatibility](/releases-and-reference/compatibility.md) so an integrator knows what to move off and what to move to. The supported SDK is the current version delivered through onboarding, identified in [Compatibility](/releases-and-reference/compatibility.md) (`Game.Sdk` on `net10.0`, delivered rather than published to a package feed); there is no separate older public version to keep running in parallel. The length of the migration window is set with the partner for the specific change rather than fixed as a single public period; a fixed default notice period is not committed here, and any contractual exception is handled in the onboarding agreement.

Changes that affect integrators are recorded in the [Release notes](/releases-and-reference/release-notes.md); the current integration surface and its stability posture are in [Compatibility](/releases-and-reference/compatibility.md).