The chain

The arrangement of session-flow's skills so that each stage produces the artifacts the next one consumes.

Work enters through a gatekeeper, passes through research and design, gets broken into session-sized tasks, is dispatched to agents, comes back for simplification and review, can go through verification, and ends at a release.

The property I would defend hardest is that the chain is composable rather than mandatory. Every stage declares what it consumes, so you enter at whichever one your work is already ready for: an existing backlog gets the next-task skill, a bug gets the debug skill and nothing before it.