DL-085
The agent persists nothing: an injected emit-backend on the SDK createAgentSession({ sessionManager }) seam turns every committed session entry into a durable TranscriptEntry AgentFrame variant (entry_json verbatim, checkpoint discriminator for SDK full-body rewrites, agent-stamped entry_seq) on the delivered-or-erred, idempotency-keyed PostConversationFrame lane — awaited per-path for per-session send order; the local SessionManager is ephemeral and dies with the container. Writer fencing is force-teardown (primary) + the durable lane’s idempotency keys and entry_seq (belt); the S3 epoch-token fence is retired with the object model
Status: Superseded by DL-089 (Matt, 2026-07-31)