Work through tasks on a kanban board stored in OpenViking (viking://agent/kanban/<board>/, one markdown file per task). Use when the user says "ov kanban", "kanban", "看板", asks to put a task on the board, hand off the current work, continue a task another agent started, or run an unattended task loop. A board holds many tasks; each task file is the handoff itself - a frontmatter header (id, status, owner, board) plus Goal, Context, Decisions, Progress, Next, Questions, Log - and its process detail is folded into an archive file instead of being summarized away, so any agent with the `ov` CLI can resume it and drill down when needed.