{
  "schemaVersion": 1,
  "slug": "fixed-spool-ribbon-unwind",
  "ownerPath": "/templates/fixed-spool-ribbon-unwind",
  "semanticKey": "one ribbon transfers from visible coil to free span around a fixed-axis rotating spool",
  "demand": {
    "type": "independent-product-lookup-value",
    "historicalExactQuery": null,
    "exactSearchVolume": null,
    "rationale": "Show a strip becoming free because it unwinds from an existing coil. A spinning disc with a stretching tail is a common-looking substitute, but it does not explain where the additional ribbon came from. Keep the transfer point visible throughout one short pull.",
    "status": "author-proposed; independent admission pending"
  },
  "input": "first-frame.png",
  "inputRoles": {
    "first-frame": "one authored PNG",
    "last-frame": null,
    "guide": "review only; do not upload"
  },
  "constraints": [
    "The hub center and stand stay fixed while the radial mark turns.",
    "The coral tab moves right without changing into a second free end.",
    "Ribbon leaves the existing outer wrap at one visible tangent region.",
    "The free span lengthens while the wound region releases material; the strip does not simply stretch.",
    "Both ribbon edges remain continuous with coherent width and no detached duplicate.",
    "The ending retains a partly wound spool and one connected free span."
  ],
  "steps": [
    "Trace the ribbon from its outer wrap to the end tab before generating. There must be one connected route with no separate floating ribbon piece.",
    "Pull the tab right while the hub turns in the matching unwinding direction. Request only enough travel to expose a readable change at the outer wrap, without emptying the spool.",
    "Compare the coil boundary, departure point and free length at the same pauses. A longer tail alone fails if the wheel mark is stationary and the ribbon merely elongates."
  ],
  "nearestOwners": [
    "/templates/cylinder-roll-translate-rotate",
    "/templates/cord-through-fixed-eyelet"
  ],
  "substantiveDifference": "The rolling-cylinder owner moves a rigid center across a floor without releasing material. The eyelet owner feeds cord through a stationary aperture. Here the center is fixed, a wound layer changes, and the free ribbon must originate at a rotating coil boundary.",
  "modelExecution": {
    "performed": false,
    "taskId": null,
    "result": null,
    "paidCalls": 0
  },
  "sourceType": "original-local-deterministic-illustration",
  "rights": "Original authored geometry and prose; no third-party media. Independent review pending."
}