{
  "title": "Coal mining support interval records for AI",
  "source_page": "https://fiund.com/industries/coal-support-sample-interval-data",
  "authorship": "Original fictional Fiund editorial exercise. No actual operating records or third-party source assets are included.",
  "example": {
    "title": "An overlapping interval is not the same service interval",
    "context": "An imaginary support contractor receives abstract interval labels measured on a practice ruler. They do not describe a mine, a seam, a depth or a real location.",
    "records": [
      [
        "CS1",
        "Practice service note",
        "Service window I-A covers ruler marks 10–20 and names bag A."
      ],
      [
        "CS2",
        "Practice sampling card",
        "Sampling interval I-B covers marks 15–25 and names bag B."
      ],
      [
        "CS3",
        "Fictional handoff receipt",
        "The receiver confirms bag B from I-B. No receipt for bag A is included."
      ]
    ],
    "question": "Which interval has a confirmed bag handoff, and does the overlap establish a handoff or shared result for I-A?",
    "answer": "CS2 and CS3 identify a confirmed handoff of bag B from I-B, spanning marks 15–25. CS1 identifies service activity for I-A and bag A, but no supplied receipt confirms that bag's transfer. The intervals overlap from 15 to 20; overlap does not make them identical or establish that either bag represents the other's full interval.",
    "failureModes": [
      "Marking I-A as received because part of its interval overlaps I-B.",
      "Combining the two interval endpoints into a new 10–25 sample unsupported by any record."
    ],
    "fields": [
      [
        "Interval endpoints and coordinate convention",
        "Preserves what each abstract interval actually covers."
      ],
      [
        "Service-note versus sample-record role",
        "Separates contractor activity from material identity."
      ],
      [
        "Bag-to-interval link",
        "Connects the handoff to the correct portion."
      ],
      [
        "Receipt state",
        "Makes missing receipt evidence visible."
      ]
    ],
    "holdout": "Add a receipt naming bag A but omit its interval reference, then introduce another bag A from a different practice job. Require a job-specific link before closing the custody gap.",
    "boundary": "Use paper records and a tabletop ruler only. Do not include mine coordinates, geology, client reports, operating methods, workers or safety-system information."
  }
}