fix: validate scraper metric semantics

scrapers/history_collector.py

@@ -114,8 +114,15 @@ def collect_onchain_history(progress_cb=None):
 
             for metric_key, trace_name in cfg["traces"].items():
                 if trace_name is None:
-                    # Grab first trace with numeric data
-                    for candidate in traces:
+                    if metric_key == "lth_supply":
+                        from scrapers.lookintobitcoin import _find_lth_supply_trace
+                        candidates = [_find_lth_supply_trace(traces)]
+                    else:
+                        candidates = traces
+                    # Grab the first validated trace with numeric data.
+                    for candidate in candidates:
+                        if not candidate:
+                            continue
                         y = candidate.get("y", [])
                         if y and any(v is not None for v in y[-10:]):
                             dates, values = _extract_series(candidate)

scrapers/lookintobitcoin.py

@@ -115,6 +115,30 @@ def _find_trace(traces, name):
     return None
 
 
+def _trace_signal_is_active(trace):
+    """Return true only when the signal trace is active at its latest point."""
+    if not trace:
+        return False
+    values = trace.get("y", [])
+    if not values:
+        return False
+    latest = values[-1]
+    try:
+        return latest is not None and float(latest) != 0
+    except (TypeError, ValueError):
+        return bool(latest)
+
+
+def _find_lth_supply_trace(traces):
+    """Select an explicitly named LTH supply series and never a price fallback."""
+    for trace in traces or []:
+        name = str(trace.get("name", "")).lower()
+        is_lth = "long-term holder" in name or "long term holder" in name or "lth" in name
+        if is_lth and "supply" in name and "price" not in name:
+            return trace
+    return None
+
+
 def _get_latest_value(trace):
     """Get the most recent non-null y value from a trace."""
     if not trace:
@@ -210,21 +234,16 @@ def scrape_all():
                     ],
                     "value": None,
                 }
-                # Try to detect buy signal from trace names/colors
+                # A named signal trace is not itself proof that the signal is active.
                 for t in traces:
                     name = t.get("name", "").lower()
-                    if "buy" in name or "signal" in name:
+                    if ("buy" in name or "signal" in name) and _trace_signal_is_active(t):
                         results[metric_key]["buy_signal"] = True
                         break
 
             elif metric_key == "lth_supply":
-                # Get main supply trace
-                t = traces[0] if traces else None
-                for candidate in traces:
-                    name = candidate.get("name", "").lower()
-                    if "supply" in name or "lth" in name:
-                        t = candidate
-                        break
+                # Require an explicitly named LTH supply trace; price is not supply.
+                t = _find_lth_supply_trace(traces)
                 recent = _get_recent_values(t, 60)
                 # Determine trend: compare recent avg to older avg
                 trend = None