DL-136
Channel post authority and forced subscription are channel-level policy fields (post_policy OPEN/OWNER_ONLY + owner_account_id + mandatory_subscription), never a ChannelKind or a visibility overload; mandatory_subscription is enforced read-side as a third disjunct in D1’s subscriber resolution; an owner/operator SetChannelPolicy (create-or-update) is the only post-creation mutation path, its txn seeding delivery cursors for every member a mandatory flip newly targets. A Manager’s coordination channel is auto-provisioned on first report gained via a reconciler hooked at the two store-level writers of agent_accounts.parent_agent_id (store.CreateAgent, store.ReparentAgent) — covering spawn, public CreateAgent, reparent, and any future writer by construction; resume on name-collision is ownership-checked (never adopts a user-created channel); membership reconciles with tree edges; dormant channels are never deleted (accepted MVP accretion). The coordination channel is OWNER_ONLY + mandatory-subscribe — a one-way manager→reports directive surface; report→manager and lateral coordination flows through DMs/group DMs, and agents at every level heavily prefer direct DMs/small targeted group DMs to keep coordination-token-cost low (standing directive, Matt). Precursor primitive to RIG-1622, not part of it. RIG-1722
Status: Active (Matt, 2026-07-31)