{
  "schemaVersion": 1,
  "slug": "ratchet-pawl-advance-hold",
  "ownerPath": "/templates/ratchet-pawl-advance-hold",
  "semanticKey": "one toothed wheel advances under one hinged pawl then is visibly blocked on a small reverse attempt",
  "demand": {
    "type": "independent-product-lookup-value",
    "historicalExactQuery": null,
    "exactSearchVolume": null,
    "rationale": "Make one-way engagement readable in a small mechanism close-up. Continuous spinning says little about whether a pawl can lift over a sloping tooth and then meet a blocking face. The requested output is one advance-and-hold event, not a running machine.",
    "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 wheel axle and pawl pivot stay fixed and separate.",
    "The pawl lifts by rotating around its pivot as the sloping tooth face arrives.",
    "The same tip settles into the next existing valley without a new tooth appearing.",
    "A small reverse attempt brings the steep face into tip contact before the wheel stops.",
    "The pale mark does not continue rotating backward through the blocking contact.",
    "The final image retains one wheel and one engaged pawl, without fused silhouettes."
  ],
  "steps": [
    "Identify the sloping approach face and steep blocking face next to the pawl tip. A symmetric decorative cog is unsuitable because it does not show the two different contacts.",
    "Request a short advance in the direction that lifts the pawl over the sloping face, then let it settle in the next valley. Include only a tiny reverse attempt to expose the blocking contact.",
    "Review the tip lifting, settling and meeting the steep face. Follow the pale mark during the reverse attempt; the wheel must stop at contact rather than continue through the pawl."
  ],
  "nearestOwners": [
    "/templates/paired-gears-opposite-rotation",
    "/templates/crank-slider-linked-stroke"
  ],
  "substantiveDifference": "Two gears continuously coordinate opposite rotations; a crank-slider keeps a connecting rod joined at both ends. This task instead uses intermittent separation and reseating of one free pawl tip, followed by a blocked reverse attempt. Neither old acceptance set checks this directional gate.",
  "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.",
  "revision": {
    "id": "wave1-r2",
    "reason": "Independent review found filled pawl/wheel overlap. Narrow pawl polygon to the unchanged valley contact; wheel, pivot, prompts and owner intent remain unchanged."
  },
  "inputBinding": {
    "pngSha256": "f2302e273d0b1086e04e9992cd17cf56a1988cc7152196eb38f6877279060ab9",
    "geometrySha256": "b465083cd54bd90a938c152a9d877b14ee4526d7268db6a65c632a52392da732"
  }
}