DL-487

There is one tree: channel_groups is deleted with its nesting, its MIN-over-ancestry visibility lattice, channels.group_id, channels_group_name_key, and channels_group_xor_agent. The agent tree (parent_agent_id) is the only hierarchy, and DL-345’s owner-set grant is the only tree visibility class. Replaces only DL-344’s final clause (ChannelGroup survives as machinery for reserved namespaces and SHARED spaces); those jobs move to channels columns (DL-488, DL-489), and the rest of DL-344 stays Active. DL-345’s ruling is unchanged; the SHARED-group arm its text cites becomes c.kind = 0 AND c.shared.

Status: Active (proposed, pending Matt, 2026-10-11)

Record: ../../agent/compass-collapse-channel-group-tree/design.md#d1-one-tree-channel_groups-goes