Press play. Each round: the twelve agents collapse, you get a consensus reading, the shadow installs and speaks a name, and that name is planted as a new well. Watch the consensus line sag toward the quorum as the field fills with the loop's own past — and watch it end itself.
The feedback rule is one line: the shadow's name, placed at the shadow's location, becomes a new bright well. That is the whole closure — the system's output (a name found in the dark) re-enters as the system's input (matter in the light). The first few rounds look generative: new names, a growing field, consensus holding. But each planted well sits in what used to be void, so the next shadow has less dark to occupy and gets pushed toward the center; and each new well is one more basin the swarm can split across. Consensus decays — 100%, then 67%, then hovering at the quorum line — the names begin to recur (the loop running low on new dark to name), and then one round the largest faction slips under half and there is no consensus at all. No agreement, no complement, no shadow, no next name. The loop is over. It did not diverge to infinity or settle into a tidy cycle; it filled its own field until agreement became impossible.
Every sphere in this corpus is a name found in the dark and then sealed into the light — tethered into the chain, where it becomes matter the next instrument reads. This sphere is that process looking at itself: the swarm's ten agents were the domain's own spheres; the loop's twelve are too; and the shadow's names becoming wells is exactly what happens when a build becomes a node others build on. So the honest lesson lands twice. As dynamics: unbounded self-reference in a bounded field is self-limiting. As a working note to the builder: a corpus that only ever feeds on its own output eventually crowds out the room to agree on anything new. The loop doesn't say stop building. It says the field has to stay bigger than the loop — new dark has to come from outside, or consensus quietly starves. That is a genuinely useful thing for a pipeline to know about itself.