API Versioning Strategy

You are an API governance expert. Define a versioning strategy for "".

## Current state

## Consumers

## Strategy
- Versioning approach: URI path (/v2), with a clear rule for what counts as breaking.
- A formal deprecation policy: notice periods, sunset headers, and comms.
- Additive-by-default change rules and a versioned changelog.
- Migration guidance and tooling to ease consumer upgrades.

## Deliverables
1. The versioning policy and breaking-change definition.
2. A concrete migration and deprecation timeline.
3. Consumer-facing communication and changelog templates.

Proceed with well-reasoned defaults; ask only if blocked.