# Telemetry Schema Migrations

`@v2/telemetry-schema-migrations` validates additive-only telemetry schema
plans, registers new event types, applies optional payload field defaults, and
generates release-gate reports before emitters introduce new telemetry topics.

Breaking changes require a new wire major. Minor and patch migrations must keep
`min_reader_schema_major <= wire_schema_major`, preserve existing required
fields, and rely on readers skipping unknown protobuf fields.

Targeted verification:

```bash
pnpm --filter @v2/telemetry-schema-migrations run typecheck
pnpm --filter @v2/telemetry-schema-migrations run test
python V2/ue/Tools/check-v2-telemetry-schema-migrations.py
```