TESS-MIG-001 — Retention and Legacy Deprecation Policy

Retention

Hermes is not a Mosaic persistence authority. The adapter maps runtime behavior only; it does not import or persist Hermes legacy session shapes.
Mosaic operator memory is scoped by tenant, owner, and session in packages/memory/src/operator-memory-plugin.ts; gateway session ownership is derived before that plugin is made available in apps/gateway/src/agent/agent.service.ts.
Existing Hermes archives remain in their source system under its existing retention policy. This project has no landed automatic transcript, profile, or preference migration.
Any future import requires an explicit, scoped design and redaction/provenance evidence; it must not extend packages/types with Hermes schema.

Session adapter use remains transitional until M5 qualification demonstrates the normalized provider path.
Kanban, skills, memory, tools, and cron are not deprecated into a Hermes bridge: they remain explicitly unsupported until their Mosaic-owned contracts are implemented and qualified.
A future deprecation change must remove the external binding first, retain rollback evidence, and then remove the adapter in a separately reviewed code change. It must not silently replace or widen a registered provider.