Kanban boards have stuck around because they do one thing well: show work moving from idea to delivered. As agentic coding has taken off, I keep seeing teams give agents their own lane on the board, a ready-for-agent state parked next to ready-for-human. I don't think that's right, and we already learned why.
The assignee has never been a lane. Think about how a scrum team runs: you assign a ticket to team A or developer X, and it doesn't slide into a "ready-for-X" column. It's ready. The assignee is a filter you slice the board by, not a place the work sits. Nobody ships a "ready-for-Alice" lane beside a "ready-for-Bob" lane. An agent is that same assignee, generalized to a non-human consumer. Ready is ready. The thing that picks it up is a filter slice.
This isn't just tidier, it's cheaper where it counts. A triage vocabulary runs on a small budget of states, five or so before it stops being memorable. Spend two on ready-for-agent / `ready-for-huma