Color is not tone.
Keep both signals.

{
  "module": "Compo 29.02",
  "name": "color_tone_similarity",
  "version": "1.0-canonical",
  "canonical_main_title": "Color/tone similarity",
  "topic": "29_СХОДСТВО_И_ПОВТОРЯЕМОСТЬ",
  "scope": "EXPLICIT_UNORDERED_PAIR_COMPARISONS_FOR_COLOR_AND_TONE_CHANNELS_OVER_IMMUTABLE_29_00_FEATURE_SCHEMA_WITH_CHANNEL_LOCAL_DISTANCES_ONLY",
  "main_topic_contract": {
    "topic_title": "Сходство и повторяемость",
    "topic_goal": "Измеряет сходство по независимым каналам — shape, size, color, tone, orientation, texture/style — и формирует similarity groups без потери источника сигнала.",
    "expected_output": "SimilarityRelation[], feature distances, similarity clusters",
    "planned_files": [
      "29.00 Similarity feature schema",
      "29.01 Shape/size similarity",
      "29.02 Color/tone similarity",
      "29.03 Orientation/texture/style similarity",
      "29.04 Multi-channel groups and tests"
    ]
  },
  "ownership": {
    "owner": "Compo29.02",
    "owns": [
      "SimilarityColorTonePairRequest",
      "SimilarityColorDistanceEvidence",
      "SimilarityToneValueEvidence",
      "SimilarityFeatureDistanceDescriptor for COLOR/TONE",
      "SimilarityRelation for COLOR/TONE",
      "SimilarityColorToneRelationSet",
      "SimilarityColorToneAttachment",
      "canonical unordered subject-pair identity",
      "exact same-channel feature binding",
      "exact same-slot comparison rule",
      "owner-normalized color-distance validation",
      "normalized tone absolute-difference derivation",
      "tone-scale compatibility validation",
      "symmetric relation materialization",
      "zero-distance semantics",
      "bounded explicit pair resolution",
      "non-mutating correction request"
    ],
    "does_not_own": [
      "feature extraction",
      "color vector generation",
      "color comparator implementation internals",
      "automatic color-space selection",
      "automatic color metric selection",
      "automatic tone normalization",
      "shape/size similarity — Compo29.01",
      "orientation/texture/style similarity — Compo29.03",
      "multi-channel aggregation — Compo29.04",
      "similarity thresholds — Compo29.04",
      "similarity clusters — Compo29.04",
      "cross-channel weighting — Compo29.04",
      "automatic pair Cartesian product",
      "proximity grouping — Topic28",
      "attention flow — Topic27",
      "universal similarity quality",
      "universal beautyScore"
    ]
  },
  "supported_channels": [
    "COLOR",
    "TONE"
  ],
  "distance_kinds": [
    "OWNER_NORMALIZED_COLOR_DISTANCE",
    "ABSOLUTE_NORMALIZED_TONE_DIFFERENCE"
  ],
  "distance_semantics": {
    "color": {
      "source": "explicit owner-qualified comparator evidence",
      "range": "[0,1]",
      "zero": "identical under the named color comparator evidence",
      "one": "maximum mismatch only under the comparator owner's normalization contract",
      "color_space_inference": "NONE",
      "universal_metric_claim": false
    },
    "tone": {
      "source": "explicit normalized scalar tone-value evidence bound to TONE featureRefs",
      "formula": "abs(toneA - toneB)",
      "input_range": "[0,1]",
      "distance_range": "[0,1]",
      "zero": "equal normalized tone values in the same explicit toneScaleRef",
      "tone_scale_conversion": "NONE",
      "perceptual_law_claim": false
    },
    "relation": {
      "pair_identity": "unordered canonical subject pair A↔B",
      "symmetric": true,
      "same_channel_required": true,
      "same_feature_slot_required": true,
      "similarityScore": null,
      "thresholdDecision": null,
      "clusterMembership": "DEFERRED_TO_29_04"
    }
  },
  "policy": {
    "max_pair_requests": [
      1,
      131072
    ],
    "max_color_distance_evidence": [
      0,
      131072
    ],
    "max_tone_value_evidence": [
      0,
      262144
    ],
    "overflow": "N_A_NO_TRUNCATION",
    "duplicate_request_ref": "INVALID",
    "duplicate_channel_pair_slot_request": "INVALID",
    "duplicate_evidence_ref": "INVALID",
    "auto_pair_cartesian": false,
    "auto_color_space_selection": false,
    "auto_color_metric_selection": false,
    "auto_color_distance_computation": false,
    "auto_tone_normalization": false,
    "auto_tone_scale_conversion": false,
    "auto_cross_slot_comparison": false,
    "auto_cross_channel_aggregation": false,
    "auto_thresholding": false,
    "auto_clustering": false,
    "auto_scoring": false
  },
  "status_semantics": {
    "OK": "29.00 feature lineage resolves and requested COLOR/TONE comparison produces a valid symmetric channel-local distance",
    "N_A": "feature/evidence is missing, subject/feature/slot lineage mismatches, tone scales differ, or bounds overflow",
    "INVALID": "malformed request/evidence, duplicate identity, self-pair, tone value outside [0,1], unsupported channel, or invalid upstream schema",
    "zero": "distance 0 is a valid equality observation under the channel contract and is never substituted for N_A"
  },
  "firewalls": [
    "color distance != color similarity score",
    "tone difference != tone similarity score",
    "distance zero != N_A",
    "color distance one != universal maximum visual difference",
    "tone distance one != universal maximum perceptual tone difference",
    "same color slot != same color value",
    "same tone slot != same tone value",
    "same feature presence != similarity",
    "feature distance != threshold decision",
    "SimilarityRelation != similarity cluster",
    "COLOR relation != TONE relation",
    "color and tone relations cannot be averaged automatically",
    "pair request != Cartesian pair generation",
    "same-slot comparison != cross-slot inference",
    "tone-scale mismatch != automatic conversion",
    "missing tone != tone zero",
    "Topic29 similarity != Topic28 proximity",
    "Topic29 similarity relation != Topic28 neighbor relation",
    "Topic29 similarity != Topic27 attention flow",
    "N_A != 0",
    "INVALID != 0",
    "descriptor != score",
    "local != global",
    "geometry != interpretation",
    "heuristic != law",
    "no universal similarity threshold",
    "no universal beautyScore"
  ],
  "owns_metrics": [],
  "independent_numeric_votes": 0,
  "topic29ProgressAfterThisModule": "3/5 local",
  "next_module": "Compo 29.03 — Orientation/texture/style similarity",
  "topic30_started": false,
  "publication": "NOT_VERIFIED"
}