diff --git a/scripts/backfill_capability_facets.py b/scripts/backfill_capability_facets.py
index b8e89d6..291b185 100644
--- a/scripts/backfill_capability_facets.py
+++ b/scripts/backfill_capability_facets.py
@@ -1,62 +1,109 @@
 #!/usr/bin/env python3
-# backfill_capability_facets.py
-import os, math
+# -*- coding: utf-8 -*-
+"""
+Idempotentes Backfill-Skript für Capability-Facetten in Qdrant.
+
+- Kompatibel mit qdrant-client 1.15.x: **kein** WithPayloadSelector-Import nötig
+- Liest alle Punkte der Collection mit Payload (scroll, with_payload=True)
+- Schreibt folgende Felder pro Point nach:
+  * capability_keys
+  * capability_ge1 .. capability_ge5
+  * capability_eq1 .. capability_eq5
+
+Hinweis: Das Skript setzt KEINE Vektoren neu, es aktualisiert nur Payload-Felder.
+"""
+
+import os
+from typing import Dict, Any, List, Tuple, Optional
 from qdrant_client import QdrantClient
-from qdrant_client.models import Filter, WithPayloadSelector
+from qdrant_client.models import Filter  # nur für API-Kompatibilität; wird hier leer genutzt
 
 COLL = os.getenv("EXERCISE_COLLECTION", "exercises")
-client = QdrantClient(host=os.getenv("QDRANT_HOST","localhost"), port=int(os.getenv("QDRANT_PORT","6333")))
+QDRANT_HOST = os.getenv("QDRANT_HOST", "localhost")
+QDRANT_PORT = int(os.getenv("QDRANT_PORT", "6333"))
+BATCH = int(os.getenv("BACKFILL_BATCH", "256"))
 
-def names_ge(caps, n):
-    out=[]
-    for k,v in (caps or {}).items():
-        try:
-            if int(v) >= n:
-                out.append(k)
-        except Exception:
-            pass
-    return sorted(out)
 
-scroll_filter = Filter(must=[])  # alles
-offset = None
-updated = 0
+def _facet_capabilities(caps: Dict[str, Any]) -> Dict[str, List[str]]:
+    caps = caps or {}
 
-while True:
-    res = client.scroll(
-        collection_name=COLL,
-        scroll_filter=scroll_filter,
-        with_payload=WithPayloadSelector(enable=True),
-        limit=256,
-        offset=offset
-    )
-    points, offset = res
-    if not points:
-        break
+    def names_where(pred) -> List[str]:
+        out = []
+        for k, v in caps.items():
+            try:
+                iv = int(v)
+            except Exception:
+                iv = 0
+            if pred(iv):
+                s = str(k).strip()
+                if s:
+                    out.append(s)
+        # stabil sortieren
+        return sorted({s for s in out}, key=str.casefold)
 
-    set_list = []
-    for pt in points:
-        p = pt.payload or {}
-        caps = p.get("capabilities") or {}
+    all_keys = sorted({str(k).strip() for k in caps.keys() if str(k).strip()}, key=str.casefold)
 
-        cap_keys = sorted([k for k in caps.keys() if k])
-        ge1 = names_ge(caps, 1)
-        ge2 = names_ge(caps, 2)
-        ge3 = names_ge(caps, 3)
+    return {
+        "capability_keys": all_keys,
+        # >= N
+        "capability_ge1": names_where(lambda lv: lv >= 1),
+        "capability_ge2": names_where(lambda lv: lv >= 2),
+        "capability_ge3": names_where(lambda lv: lv >= 3),
+        "capability_ge4": names_where(lambda lv: lv >= 4),
+        "capability_ge5": names_where(lambda lv: lv >= 5),
+        # == N
+        "capability_eq1": names_where(lambda lv: lv == 1),
+        "capability_eq2": names_where(lambda lv: lv == 2),
+        "capability_eq3": names_where(lambda lv: lv == 3),
+        "capability_eq4": names_where(lambda lv: lv == 4),
+        "capability_eq5": names_where(lambda lv: lv == 5),
+    }
 
-        # nur setzen, wenn fehlt oder abweicht
-        if p.get("capability_keys") != cap_keys or p.get("capability_ge1") != ge1 \
-           or p.get("capability_ge2") != ge2 or p.get("capability_ge3") != ge3:
-            set_list.append((pt.id, {
-                "capability_keys": cap_keys,
-                "capability_ge1": ge1,
-                "capability_ge2": ge2,
-                "capability_ge3": ge3
-            }))
 
-    if set_list:
-        client.set_payload(collection_name=COLL, payload={pid: pay for pid, pay in set_list}, points=[pid for pid,_ in set_list])
-        updated += len(set_list)
-        print(f"[Backfill] updated {len(set_list)} points…")
+def main() -> None:
+    client = QdrantClient(host=QDRANT_HOST, port=QDRANT_PORT)
 
-print(f"[Backfill] done. total={updated}")
+    # Sanity: Collection muss existieren
+    info = client.get_collection(COLL)
+    print(f"[Backfill] Collection '{COLL}' ok – vectors={info.config.params.vectors}")
 
+    updated = 0
+    offset = None
+    page = 0
+
+    while True:
+        page += 1
+        points, offset = client.scroll(
+            collection_name=COLL,
+            scroll_filter=None,        # alles
+            offset=offset,
+            limit=BATCH,
+            with_payload=True,
+        )
+        if not points:
+            break
+
+        for pt in points:
+            pld = pt.payload or {}
+            caps = pld.get("capabilities") or {}
+            facets = _facet_capabilities(caps)
+
+            # Nur schreiben, wenn sich etwas ändert oder Felder fehlen
+            need = False
+            for k, v in facets.items():
+                if pld.get(k) != v:
+                    need = True
+                    break
+            if not need:
+                continue
+
+            # set_payload: pro Punkt separat (per-Point Payload)
+            client.set_payload(collection_name=COLL, points=[pt.id], payload=facets)
+            updated += 1
+        print(f"[Backfill] page={page} processed={len(points)} updated_total={updated}")
+
+    print(f"[Backfill] done. total_updated={updated}")
+
+
+if __name__ == "__main__":
+    main()