{
 "schema_version": "0.1",
 "name": "[[8,3,2]] coupled pair of 422 blocks",
 "code_type": "CSS",
 "n": 8,
 "k": 3,
 "checks": {
  "X": [
   [
    0,
    1,
    2,
    3
   ],
   [
    4,
    5,
    6,
    7
   ],
   [
    0,
    1,
    4,
    5
   ]
  ],
  "Z": [
   [
    0,
    1,
    2,
    3
   ],
   [
    4,
    5,
    6,
    7
   ]
  ]
 },
 "distance": {
  "d": 2,
  "X": {
   "value": 2,
   "confidence": "upper_bound",
   "witness": [
    6,
    7
   ]
  },
  "Z": {
   "value": 2,
   "confidence": "upper_bound",
   "witness": [
    6,
    7
   ]
  }
 },
 "provenance": {
  "authors": [
   "@mathysrennela"
  ],
  "construction": "Start with two [[4,2,2]] plaquette codes on adjacent 2x2 squares. Deform by adding one X-type stabilizer equal to the product of the same weight-2 logical X representative on each block (supports [0,1,4,5]); retain both block stabilizer pairs. The added local check couples the blocks, so this is not a direct sum.",
  "references": [],
  "model": "GPT-6 Luna",
  "date": "2026-09-23",
  "notes": "Checked against the board: no exact or Weisfeiler-Lehman equivalent entry. See notes/8-3-2.md."
 },
 "family": "other",
 "locality": {
  "coordinates": [
   [
    0.0,
    0.0
   ],
   [
    0.0,
    1.0
   ],
   [
    1.0,
    0.0
   ],
   [
    1.0,
    1.0
   ],
   [
    2.0,
    0.0
   ],
   [
    2.0,
    1.0
   ],
   [
    3.0,
    0.0
   ],
   [
    3.0,
    1.0
   ]
  ],
  "interaction_radius": 2.23606797749979,
  "layers": 1
 }
}