fix(agents): Impressum+Cookie delegieren MC-Laden ans Main Tool — Scope-Filter + Maßnahmen

Regression: Der v3-Agent-Pfad baute eine parallele MC-Pipeline (_load_impressum_mcs / _load_cookie_mcs, Roh-SELECT) und lief damit an allen Schutzmechanismen der Engine vorbei → GOV/Branchen-MCs als HIGH bei OEM/Zulieferer, fremde MCs (Bestellbestätigung), und action=check_question (Fragen statt Maßnahmen im Frontend). - Agent delegiert MC-Laden an rag_document_checker._load_controls (P72-Scope, check_type='text', fits_doc_type/scope_requires). - Subtraktives Sektor-Gate (SECTOR_PREFIXES) + Themen-Gate am Agent-Rand. - action = konkrete Maßnahme (Imperativ) statt check_question. - rag_document_checker: from __future__ import annotations (3.9-Import). - mcs: Name-Pattern erkennt "Aktiengesellschaft" (OEM-Impressums). - Tote GT-/Semantic-/Routes-Tests wiederbelebt (v3-Mismatch + agent.cascade-Patch-Target). Alle 72 Specialist-Tests grün. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-09 11:30:16 +02:00
parent bd4882e143
commit 389e6de0c7
13 changed files with 641 additions and 135 deletions
@@ -14,6 +14,11 @@ Flow:
    → Returns structured results compatible with CheckItem format
 """

+# Lazy annotations: dieses Modul nutzt PEP-604-Hints (z.B. `set[str] | None`)
+# und muss auch auf Python 3.9 importierbar bleiben (lokale Tests / safe-
+# import in compliance.api). Keine Pydantic-Modelle hier — daher unkritisch.
+from __future__ import annotations
+
 import logging
 import os
 import re
@@ -44,6 +44,19 @@ _SEV_TO_ENUM = {
 }


+def _build_measure(label: str, norm: str) -> str:
+    """Maßnahme (Imperativ) statt Pruef-Frage als action. Das Tool
+    definiert Maßnahmen im Frontend — es stellt keine Fragen."""
+    base = (label or "").strip().rstrip(".")
+    if not base:
+        return ("Cookie-Angabe ergänzen und gegen die gesetzlichen "
+                "Vorgaben prüfen.")
+    msg = f"Cookie-Angabe ergänzen: {base}."
+    if norm:
+        msg += f" Rechtsgrundlage: {norm}."
+    return msg
+
+
 class CookiePolicyAgent(BaseSpecialistAgent):
    agent_id = "cookie_policy"
    agent_version = "3.0"
@@ -77,6 +90,11 @@ class CookiePolicyAgent(BaseSpecialistAgent):
            f"{telemetry.get('layer_0_field_hits', 0)} Pattern-Boosts · "
            f"{telemetry.get('layer_0_boost_overrides', 0)} Boost-Overrides"
        )
+        if telemetry.get("sector_dropped"):
+            notes_parts.append(
+                f"Scope-Filter: {telemetry['sector_dropped']} "
+                "Branchen-MCs entfernt"
+            )

        seen: set[str] = set()
        for r in results:
@@ -96,6 +114,9 @@ class CookiePolicyAgent(BaseSpecialistAgent):
            if passed:
                continue
            label = r.get("label") or r.get("hint") or ""
+            norm_str = str(r.get("regulation") or "")
+            if r.get("article"):
+                norm_str = (norm_str + f" Art. {r.get('article')}").strip()
            findings.append(Finding(
                check_id=f"DBMC-{mc_id}",
                agent=self.agent_id,
@@ -104,12 +125,9 @@ class CookiePolicyAgent(BaseSpecialistAgent):
                severity=sev,
                severity_reason="db_mc_failed",
                title=str(label)[:200] or f"DB-MC {mc_id} nicht erfüllt",
-                norm=str(r.get("regulation") or "") +
-                      (f" Art. {r.get('article')}"
-                       if r.get("article") else ""),
+                norm=norm_str,
                evidence="",
-                action=str(r.get("hint") or "")[:400]
-                       or "Bitte gegen die Cookie-Pflichten prüfen.",
+                action=_build_measure(str(label), norm_str)[:400],
                confidence=0.9,
                sources=[EvidenceSource(
                    source_type=SourceType.MC,
@@ -1,7 +1,10 @@
 """Cookie-Policy v3-Pipeline — analog zu impressum/v3_engine.py.

-Lädt 381 Cookie-MCs aus compliance.doc_check_controls (doc_type='cookie'),
-ruft den deterministischen Keyword-Check + Embedding-Match + Boost-Override.
+MC-Laden DELEGIERT an die Main-Tool-Engine (rag_document_checker._load_controls,
+doc_type='cookie'): eine Quelle der Wahrheit inkl. P72-Scope, check_type='text'
+und fits_doc_type/scope_requires. KEINE parallele Roh-Query mehr. Danach
+deterministischer Keyword-Check + Embedding-Match + Boost-Override.
+Zusaetzlich ein subtraktives Sektor-Gate (Branchen-Prefix) am Agent-Rand.
 """

 from __future__ import annotations
@@ -13,9 +16,17 @@ from .regex_boost import boost_matches_db_mc, compute_regex_boosts

 logger = logging.getLogger(__name__)

+# Branchen-Prefix -> erwarteter Scope-Token (reuse aus dem Mail-V2-Filter).
+try:
+    from compliance.services.mail_render_v2._scope_filter import (
+        SECTOR_PREFIXES,
+    )
+except Exception:  # pragma: no cover
+    SECTOR_PREFIXES = {}
+

 async def run_v3_pipeline(
-    text: str, business_scope: set[str],
+    text: str, business_scope: set[str], db_url: str = "",
 ) -> tuple[list[dict[str, Any]], dict[str, Any]]:
    if not text or len(text) < 100:
        return [], {"reason": "text too short"}
@@ -24,8 +35,16 @@ async def run_v3_pipeline(
    boosts = compute_regex_boosts(text)
    boost_field_ids = sorted(boosts)

-    # Layer 1: alle 381 Cookie-MCs aus DB laden
-    controls = await _load_cookie_mcs()
+    # Layer 1: MC-Laden DELEGIERT an die Main-Tool-Engine (Scope-Schutz
+    # inklusive). Danach subtraktives Sektor-Gate am Agent-Rand.
+    try:
+        from compliance.services.rag_document_checker import _load_controls
+        controls = await _load_controls("cookie", db_url, 0, business_scope)
+    except Exception as e:
+        logger.warning("cookie v3 load via main-tool engine failed: %s", e)
+        controls = []
+    _normalize_criteria(controls)
+    controls, sector_dropped = _filter_sector(controls, business_scope)
    results: list[dict[str, Any]] = []
    if controls:
        try:
@@ -91,51 +110,50 @@ async def run_v3_pipeline(
        "layer_1_pass": layer_1_pass,
        "layer_0_boost_overrides": boost_overrides,
        "total_mcs": len(results),
+        "sector_dropped": sector_dropped,
    }
    return results, telemetry


-async def _load_cookie_mcs() -> list[dict]:
-    """Lädt alle 381 Cookie-MCs aus compliance.doc_check_controls."""
-    try:
-        import json
-        from classroom_engine.database import SessionLocal
-        from sqlalchemy import text as _sa_text
-        db = SessionLocal()
-        try:
-            rows = db.execute(_sa_text(
-                "SELECT id, control_id, control_uuid, title, regulation, "
-                "       article, check_question, pass_criteria, "
-                "       fail_criteria, severity "
-                "FROM compliance.doc_check_controls "
-                "WHERE doc_type='cookie' "
-                "ORDER BY severity DESC, title"
-            )).fetchall()
-        finally:
-            db.close()
-        out = []
-        for r in rows:
-            def _parse(v):
-                if isinstance(v, list): return v
-                if isinstance(v, str):
-                    try:
-                        j = json.loads(v)
-                        return j if isinstance(j, list) else [v]
-                    except Exception: return [v]
-                return []
-            out.append({
-                "id": str(r[0]),
-                "control_id": r[1],
-                "control_uuid": str(r[2]) if r[2] else "",
-                "title": r[3] or "",
-                "regulation": r[4] or "",
-                "article": r[5] or "",
-                "check_question": r[6] or "",
-                "pass_criteria": _parse(r[7]),
-                "fail_criteria": _parse(r[8]),
-                "severity": r[9] or "MEDIUM",
-            })
-        return out
-    except Exception as e:
-        logger.warning("_load_cookie_mcs failed: %s", e)
-        return []
+def _normalize_criteria(controls: list[dict[str, Any]]) -> None:
+    """asyncpg liefert JSONB-Spalten als Roh-String → zu Listen parsen."""
+    import json
+    for c in controls:
+        for key in ("pass_criteria", "fail_criteria"):
+            v = c.get(key)
+            if isinstance(v, list):
+                continue
+            if isinstance(v, str):
+                try:
+                    parsed = json.loads(v)
+                    c[key] = parsed if isinstance(parsed, list) else [v]
+                except Exception:
+                    c[key] = [v] if v else []
+            else:
+                c[key] = []
+
+
+def _filter_sector(
+    controls: list[dict[str, Any]],
+    business_scope: set[str],
+) -> tuple[list[dict[str, Any]], int]:
+    """Subtraktives Sektor-Gate: MCs deren control_id-Prefix eine Branche
+    bezeichnet (FIN/GOV/MED/INS/EDU/LEG/REL/POL), die NICHT im business_scope
+    liegt, werden verworfen — sonst tauchen z.B. GOV-MCs bei einem
+    OEM/Zulieferer als Finding auf. Reuse der SECTOR_PREFIXES."""
+    scope_lc = {s.lower() for s in (business_scope or set())}
+    kept: list[dict[str, Any]] = []
+    dropped = 0
+    for c in controls:
+        cid = c.get("control_id") or ""
+        prefix = cid.split("-")[0].upper() if "-" in cid else ""
+        required = SECTOR_PREFIXES.get(prefix)
+        if required and not (scope_lc & required):
+            dropped += 1
+            continue
+        kept.append(c)
+    if dropped:
+        logger.info("cookie v3 sector-filter: -%d Branchen-MCs", dropped)
+    return kept, dropped
+
+
@@ -54,6 +54,24 @@ _SEV_TO_ENUM = {
 }


+def _build_measure(label: str, norm: str) -> str:
+    """Formuliert aus einer fehlenden Pflichtangabe eine konkrete Maßnahme
+    (Imperativ) statt die Pruef-Frage auszugeben.
+
+    Das Tool definiert Maßnahmen im Frontend — es stellt keine Fragen. Der
+    check_question-Text ('Ist X angegeben?') wird daher NICHT mehr als
+    action durchgereicht (sonst zeigt die Finding-Card eine Frage unter
+    'Pflicht-Maßnahme')."""
+    base = (label or "").strip().rstrip(".")
+    if not base:
+        return ("Pflichtangabe ergänzen und gegen die gesetzlichen "
+                "Vorgaben prüfen.")
+    msg = f"Pflichtangabe ergänzen: {base}."
+    if norm:
+        msg += f" Rechtsgrundlage: {norm}."
+    return msg
+
+
 class ImpressumAgent(BaseSpecialistAgent):
    agent_id = "impressum"
    agent_version = "3.0"
@@ -96,6 +114,13 @@ class ImpressumAgent(BaseSpecialistAgent):
            f"{telemetry.get('layer_0_field_hits', 0)} Pattern-Boosts · "
            f"{telemetry.get('layer_0_boost_overrides', 0)} Boost-Overrides"
        )
+        sec_drop = telemetry.get("sector_dropped", 0)
+        off_drop = telemetry.get("offtopic_dropped", 0)
+        if sec_drop or off_drop:
+            notes_parts.append(
+                f"Scope-Filter: {sec_drop} Branchen-MCs + "
+                f"{off_drop} themenfremde MCs entfernt"
+            )

        # DB-MCs → Findings + Coverage
        seen_db_mcs: set[str] = set()
@@ -116,6 +141,9 @@ class ImpressumAgent(BaseSpecialistAgent):
            if passed:
                continue
            label = r.get("label") or r.get("hint") or ""
+            norm_str = str(r.get("regulation") or "")
+            if r.get("article"):
+                norm_str = (norm_str + f" Art. {r.get('article')}").strip()
            findings.append(Finding(
                check_id=f"DBMC-{mc_id}",
                agent=self.agent_id,
@@ -124,12 +152,9 @@ class ImpressumAgent(BaseSpecialistAgent):
                severity=sev,
                severity_reason="db_mc_failed",
                title=str(label)[:200] or f"DB-MC {mc_id} nicht erfüllt",
-                norm=str(r.get("regulation") or "") +
-                      (f" Art. {r.get('article')}"
-                       if r.get("article") else ""),
+                norm=norm_str,
                evidence="",
-                action=str(r.get("hint") or "")[:400]
-                       or "Bitte gegen die Pflichtangaben prüfen.",
+                action=_build_measure(str(label), norm_str)[:400],
                confidence=0.9,
                sources=[EvidenceSource(
                    source_type=SourceType.MC,
@@ -43,7 +43,8 @@ MCS: tuple[MC, ...] = (
            # Label-free fallback: Firma (Rechtsform) + Adresse
            re.compile(
                r"\b[A-ZÄÖÜ][\w\-\& ]{1,80}?\s+"
-                r"(?:GmbH|AG|UG|KG|SE|GbR|OHG|Limited|Ltd|LLC)\s*"
+                r"(?:Aktiengesellschaft|GmbH|AG|UG|KG|SE|GbR|OHG|"
+                r"Limited|Ltd|LLC)\s*"
                r"[\s\S]{0,400}?"
                r"\b\d{5}\s+[A-ZÄÖÜ]",
                re.IGNORECASE,
@@ -150,3 +150,44 @@ def boost_matches_db_mc(
            if best is None or match_count > best[0]:
                best = (match_count, field_id)
    return best[1] if best else None
+
+
+def criteria_on_topic(
+    pass_criteria: list | None,
+    fail_criteria: list | None = None,
+    min_hits: int = 2,
+) -> bool:
+    """Deterministischer Themen-Gate: gehoert eine DB-MC ueberhaupt ins
+    Impressum-Themenfeld?
+
+    Prueft ob die kombinierten pass/fail_criteria mindestens `min_hits`
+    UNTERSCHIEDLICHE Schluesselwoerter aus IRGENDEINEM der 12 Impressum-
+    Felder (BOOST_KEYWORDS) enthalten. Fremd-MCs (z.B. 'Bestellbestaetigung',
+    'behoerdliche Anzeige'), die faelschlich unter doc_type='impressum'
+    getaggt sind, haben keinen Themen-Ueberlapp und werden so aussortiert
+    — unabhaengig von DB-Sidecar/Klassifikation.
+
+    Konservativ in beide Richtungen:
+      - ein einzelner inzidenteller Treffer (z.B. 'E-Mail' in einer
+        Bestellbestaetigung) reicht NICHT -> >=2 verschiedene Stichwoerter.
+      - leere Kriterien -> on-topic behalten (lieber ein FP als eine echte
+        Pflichtangabe verlieren).
+    """
+    crit_parts: list[str] = []
+    for c in (pass_criteria or []):
+        if c:
+            crit_parts.append(str(c).lower())
+    for c in (fail_criteria or []):
+        if c:
+            crit_parts.append(str(c).lower())
+    if not crit_parts:
+        return True
+    crit_text = " ".join(crit_parts)
+    hits: set[str] = set()
+    for kws in BOOST_KEYWORDS.values():
+        for kw in kws:
+            if kw in crit_text:
+                hits.add(kw)
+                if len(hits) >= min_hits:
+                    return True
+    return False
@@ -1,17 +1,20 @@
-"""Sprint-1.12 v3-Engine: läuft die volle 4-Layer-Pipeline auf einem
-Impressum-Text:
+"""v3-Engine: läuft die 4-Layer-Pipeline auf einem Impressum-Text.

-  Layer 0  — Regex-Boost (meine 12 Patterns aus mcs.py)
-  Layer 1  — Keyword-Match aus doc_check_controls.pass_criteria
-              (75 MCs in DB für Impressum)
-  Layer 2  — BGE-M3 Embedding-Match als Fallback (im
-              rag_document_checker integriert)
-  Layer 3  — Semantic-Validator (LLM) wenn auch Embedding nicht half
-              (im Agent angefasst, hier nur Ergebnisse durchgereicht)
+  Layer 0  — Regex-Boost (die 12 deterministischen Agent-Patterns)
+  Layer 1  — MC-Laden + Keyword-Match. Das LADEN delegiert an die
+              Main-Tool-Engine (rag_document_checker._load_controls):
+              eine Quelle der Wahrheit inkl. P72-Scope, check_type='text'
+              und fits_doc_type/scope_requires aus dem Sidecar. KEINE
+              parallele Roh-Query mehr.
+  Layer 2  — BGE-M3 Embedding-Match (mc_embedding_matcher, shared)
+  Layer 3  — Semantic-Validator (LLM) im Agent (hier nur durchgereicht)

-Output: Liste Result-Dicts kompatibel mit rag_document_checker (passed,
-severity, control_id, regulation, ...). Der Agent konvertiert sie dann
-zu Finding-Objekten.
+Zusätzlich am Agent-Rand: subtraktives Sektor-/Themen-Gate
+(_filter_controls) — das Sektor-Gate (Branchen-Prefix) macht die Engine
+nicht, es lebt sonst im Mail-V2-Report.
+
+Output: Liste Result-Dicts kompatibel mit rag_document_checker. Der Agent
+konvertiert sie zu Finding-Objekten.
 """

 from __future__ import annotations
@@ -19,10 +22,25 @@ from __future__ import annotations
 import logging
 from typing import Any

-from .regex_boost import boost_matches_db_mc, compute_regex_boosts
+from .regex_boost import (
+    boost_matches_db_mc,
+    compute_regex_boosts,
+    criteria_on_topic,
+)

 logger = logging.getLogger(__name__)

+# Branchen-Prefix -> erwarteter Scope-Token. Reuse aus dem Mail-V2-
+# Scope-Filter, damit Agent-Pfad und Report-Pfad dieselbe Quelle nutzen
+# (keine divergente Zweit-Logik). Import defensiv: faellt der Mail-Pfad
+# weg, bleibt der Agent lauffaehig (ohne Sektor-Gate).
+try:
+    from compliance.services.mail_render_v2._scope_filter import (
+        SECTOR_PREFIXES,
+    )
+except Exception:  # pragma: no cover - defensiver Fallback
+    SECTOR_PREFIXES = {}
+

 async def run_v3_pipeline(
    text: str,
@@ -43,11 +61,22 @@ async def run_v3_pipeline(
    logger.info("v3 Layer-0 boosts: %d hits — %s",
                len(boost_field_ids), boost_field_ids)

-    # Layer 1: lade ALLE 75 doc_check_controls für 'impressum' direkt
-    # aus DB. Sidecar-Klassifizierung wird bewusst übersprungen — der
-    # Agent soll auf der vollen MC-Liste arbeiten (Layer 3 LLM-Validator
-    # demoted Pattern-Misses zu LOW, sodass Breitenwirkung kein Risiko ist).
-    controls = await _load_impressum_mcs()
+    # Layer 1: MC-Laden DELEGIERT an die Main-Tool-Engine. Damit erbt der
+    # Agent automatisch deren Scope-Schutz (P72 canonical-scope,
+    # check_type='text', fits_doc_type/scope_requires) — genau die Filter,
+    # an denen die alte parallele Roh-Query vorbeilief.
+    try:
+        from compliance.services.rag_document_checker import _load_controls
+        controls = await _load_controls(
+            "impressum", db_url, 0, business_scope,
+        )
+    except Exception as e:
+        logger.warning("v3 load via main-tool engine failed: %s", e)
+        controls = []
+    _normalize_criteria(controls)
+    # Agent-Rand-Backstop (DB-unabhaengig): Sektor-Gate (Branchen-Prefix,
+    # macht die Engine nicht) + Themen-Gate (falls der Sidecar leer ist).
+    controls, drop_stats = _filter_controls(controls, business_scope)
    results: list[dict[str, Any]] = []
    if controls:
        try:
@@ -122,55 +151,73 @@ async def run_v3_pipeline(
        "layer_1_fail": layer_1_fail,
        "layer_0_boost_overrides": boost_overrides,
        "total_mcs": len(results),
+        "sector_dropped": drop_stats.get("sector_dropped", 0),
+        "offtopic_dropped": drop_stats.get("offtopic_dropped", 0),
    }
    logger.info("v3 telemetry: %s", telemetry)
    return results, telemetry


-async def _load_impressum_mcs() -> list[dict]:
-    """Lädt alle Impressum-MCs aus compliance.doc_check_controls — ohne
-    Sidecar-Filter. v3_engine nimmt die volle Breite."""
-    try:
-        import json
-        from classroom_engine.database import SessionLocal
-        from sqlalchemy import text as _sa_text
-        db = SessionLocal()
-        try:
-            rows = db.execute(_sa_text(
-                "SELECT id, control_id, control_uuid, title, regulation, "
-                "       article, check_question, pass_criteria, "
-                "       fail_criteria, severity "
-                "FROM compliance.doc_check_controls "
-                "WHERE doc_type='impressum' "
-                "ORDER BY severity DESC, title"
-            )).fetchall()
-        finally:
-            db.close()
-        out: list[dict] = []
-        for r in rows:
-            def _parse(v):
-                if isinstance(v, list):
-                    return v
-                if isinstance(v, str):
-                    try:
-                        j = json.loads(v)
-                        return j if isinstance(j, list) else [v]
-                    except Exception:
-                        return [v]
-                return []
-            out.append({
-                "id": str(r[0]),
-                "control_id": r[1],
-                "control_uuid": str(r[2]) if r[2] else "",
-                "title": r[3] or "",
-                "regulation": r[4] or "",
-                "article": r[5] or "",
-                "check_question": r[6] or "",
-                "pass_criteria": _parse(r[7]),
-                "fail_criteria": _parse(r[8]),
-                "severity": r[9] or "MEDIUM",
-            })
-        return out
-    except Exception as e:
-        logger.warning("_load_impressum_mcs failed: %s", e)
-        return []
+def _filter_controls(
+    controls: list[dict[str, Any]],
+    business_scope: set[str],
+) -> tuple[list[dict[str, Any]], dict[str, int]]:
+    """Subtraktiver Scope-Filter VOR der Bewertung.
+
+      1. Sektor-Gate — MCs deren control_id-Prefix eine Branche bezeichnet
+         (FIN/GOV/MED/INS/EDU/LEG/REL/POL), die NICHT im business_scope
+         liegt, werden verworfen. Fuer einen OEM/Zulieferer/Maschinenbauer
+         (kein Behoerden-/Finanz-/Medizin-Scope) fallen GOV/FIN/MED-MCs so
+         heraus — derselbe Mechanismus wie im Mail-V2-Report.
+      2. Themen-Gate — MCs ohne Impressum-Themenueberlapp werden verworfen
+         (faengt fremd-getaggte MCs wie 'Bestellbestaetigung').
+
+    Rein subtraktiv: entfernt nur falsch-positive Kandidaten, erzeugt nie
+    neue Findings.
+    """
+    scope_lc = {s.lower() for s in (business_scope or set())}
+    kept: list[dict[str, Any]] = []
+    sector_dropped = 0
+    offtopic_dropped = 0
+    for c in controls:
+        cid = c.get("control_id") or ""
+        prefix = cid.split("-")[0].upper() if "-" in cid else ""
+        required = SECTOR_PREFIXES.get(prefix)
+        if required and not (scope_lc & required):
+            sector_dropped += 1
+            continue
+        if not criteria_on_topic(c.get("pass_criteria"),
+                                 c.get("fail_criteria")):
+            offtopic_dropped += 1
+            continue
+        kept.append(c)
+    if sector_dropped or offtopic_dropped:
+        logger.info(
+            "v3 scope-filter: -%d Branchen-MCs, -%d themenfremde MCs "
+            "(scope=%s)", sector_dropped, offtopic_dropped,
+            sorted(scope_lc) or "leer",
+        )
+    return kept, {
+        "sector_dropped": sector_dropped,
+        "offtopic_dropped": offtopic_dropped,
+    }
+
+
+def _normalize_criteria(controls: list[dict[str, Any]]) -> None:
+    """asyncpg liefert JSONB-Spalten (pass_criteria/fail_criteria) als
+    Roh-String. In echte Listen parsen, damit Sektor-/Themen-Gate und
+    der Boost-Layer Element-weise (nicht Zeichen-weise) iterieren."""
+    import json
+    for c in controls:
+        for key in ("pass_criteria", "fail_criteria"):
+            v = c.get(key)
+            if isinstance(v, list):
+                continue
+            if isinstance(v, str):
+                try:
+                    parsed = json.loads(v)
+                    c[key] = parsed if isinstance(parsed, list) else [v]
+                except Exception:
+                    c[key] = [v] if v else []
+            else:
+                c[key] = []