feat: deterministic disputed-value detection for cluster assertions

backend/agents/disputes.py

@@ -0,0 +1,55 @@
+"""Deterministic detection of contradictory extracted values within a cluster.
+
+Extraction is a vision pass: quantities and sizes can be misread ("(2) 2x6" vs
+"(5) 2x6"). Cluster members are supposed to describe the same real-world
+element, so two members asserting different values for the same attribute are
+a probable misread. Flag these so downstream text-only stages treat the value
+as unverified instead of reasoning from one reading.
+"""
+
+import re
+from typing import Dict, List
+
+
+def _norm(value) -> str:
+    return re.sub(r"\s+", " ", str(value or "").strip().lower())
+
+
+def find_disputes(assertions: List[Dict]) -> List[Dict]:
+    """Same attribute with >= 2 distinct normalized values = disputed."""
+    groups: Dict[str, Dict[str, Dict]] = {}
+    for assertion in assertions:
+        attribute = _norm(assertion.get("attribute"))
+        value = _norm(assertion.get("value"))
+        if not attribute or not value:
+            continue
+        # Group on the normalized value, but keep the original (whitespace-
+        # collapsed) text so disputes read like the sheet, not a lowercase munge.
+        original = re.sub(r"\s+", " ", str(assertion.get("value")).strip())
+        bucket = groups.setdefault(attribute, {}).setdefault(
+            value, {"original": original, "ids": set()}
+        )
+        bucket["ids"].add(assertion.get("id"))
+    disputes = []
+    for attribute, values in sorted(groups.items()):
+        if len(values) < 2:
+            continue
+        disputes.append({
+            "attribute": attribute,
+            "values": sorted(v["original"] for v in values.values()),
+            "assertion_ids": sorted(
+                aid for v in values.values() for aid in v["ids"] if aid
+            ),
+        })
+    return disputes
+
+
+def annotate_clusters(clusters: List[Dict]) -> int:
+    """Attach disputed_attributes to each cluster that has any. Returns count."""
+    annotated = 0
+    for cluster in clusters:
+        disputes = find_disputes(cluster.get("assertions") or [])
+        if disputes:
+            cluster["disputed_attributes"] = disputes
+            annotated += 1
+    return annotated

tests/agents/test_disputes.py

@@ -0,0 +1,42 @@
+from backend.agents.disputes import annotate_clusters, find_disputes
+
+
+def _a(id_, attribute, value):
+    return {"id": id_, "attribute": attribute, "value": value,
+            "source_text": value}
+
+
+def test_find_disputes_flags_same_attribute_different_values():
+    assertions = [
+        _a("a1", "stud_pack_size", "(2) 2x6 STUD PACK"),
+        _a("a2", "stud_pack_size", "(5) 2x6 STUD PACK"),
+        _a("a3", "beam_size", "HSS16X4X5/8"),
+    ]
+    disputes = find_disputes(assertions)
+    assert len(disputes) == 1
+    assert disputes[0]["attribute"] == "stud_pack_size"
+    assert disputes[0]["values"] == ["(2) 2x6 STUD PACK", "(5) 2x6 STUD PACK"]
+    assert disputes[0]["assertion_ids"] == ["a1", "a2"]
+
+
+def test_find_disputes_ignores_agreeing_values_and_blanks():
+    assertions = [
+        _a("a1", "beam_size", "HSS16X4X5/8"),
+        _a("a2", "beam_size", "  hss16x4x5/8 "),   # same after normalize
+        _a("a3", "", "orphan"),                     # no attribute -> skipped
+        _a("a4", "beam_size", ""),                  # no value -> skipped
+    ]
+    assert find_disputes(assertions) == []
+
+
+def test_annotate_clusters_writes_disputed_attributes():
+    clusters = [
+        {"key": "c1", "assertions": [
+            _a("a1", "stud_pack_size", "(2) 2x6"),
+            _a("a2", "stud_pack_size", "(5) 2x6"),
+        ]},
+        {"key": "c2", "assertions": [_a("a3", "x", "1"), _a("a4", "x", "1")]},
+    ]
+    assert annotate_clusters(clusters) == 1
+    assert clusters[0]["disputed_attributes"][0]["attribute"] == "stud_pack_size"
+    assert "disputed_attributes" not in clusters[1]