diff --git a/tests/test_llm_bewerter.py b/tests/test_llm_bewerter.py
index 3e1ae31..2a2ff5d 100644
--- a/tests/test_llm_bewerter.py
+++ b/tests/test_llm_bewerter.py
@@ -135,3 +135,66 @@ class TestLlmRequestDefaults:
         assert req.max_retries == 3
         assert req.max_tokens == 4000
         assert req.base_temperature == 0.3
+
+
+# ─── Coverage-Backfill (#134) ────────────────────────────────────────────────
+
+
+class TestContentFingerprint:
+    def test_empty_string_returns_len_zero(self):
+        from app.adapters.qwen_bewerter import _content_fingerprint
+        assert _content_fingerprint("") == "len=0"
+
+    def test_none_returns_len_zero(self):
+        from app.adapters.qwen_bewerter import _content_fingerprint
+        # Defensiv: None toleriert, weil log-Pfad aufgerufen wird
+        # mit content.choices[0].message.content der schon mal None ist
+        assert _content_fingerprint(None) == "len=0"
+
+    def test_non_empty_includes_sha1_prefix(self):
+        from app.adapters.qwen_bewerter import _content_fingerprint
+        result = _content_fingerprint("hallo")
+        assert result.startswith("len=5 sha1=")
+        assert len(result.split("sha1=")[1]) == 8
+
+
+class TestStripMarkdownJsonFences:
+    """```json-Fence wird zusaetzlich zum Plain-Fence behandelt."""
+
+    def test_json_fence_with_explicit_lang(self):
+        from app.adapters.qwen_bewerter import _strip_markdown_fences
+        s = "```json\n{\"a\": 1}\n```"
+        assert _strip_markdown_fences(s) == '{"a": 1}'
+
+
+class TestLazyClientInstantiation:
+    """_get_client laedt openai erst beim ersten Call."""
+
+    def test_no_client_triggers_openai_import(self, monkeypatch):
+        """Wenn der Client nicht injected ist, versucht _get_client den
+        Lazy-Import von openai.AsyncOpenAI. Hier patchen wir den Import,
+        um sicherzustellen dass _get_client tatsaechlich versucht zu
+        instanziieren (Branch-Coverage Lines 70-73)."""
+        import sys
+        from unittest.mock import MagicMock
+        from app.adapters.qwen_bewerter import QwenBewerter
+
+        fake_client = MagicMock(name="AsyncOpenAI-Instance")
+        fake_async_openai = MagicMock(return_value=fake_client)
+        fake_module = type(sys)("openai")
+        fake_module.AsyncOpenAI = fake_async_openai
+        monkeypatch.setitem(sys.modules, "openai", fake_module)
+
+        qb = QwenBewerter(api_key="test", base_url="http://test")
+        client = qb._get_client()
+        assert client is fake_client
+        fake_async_openai.assert_called_once_with(api_key="test",
+                                                  base_url="http://test")
+
+    def test_injected_client_skips_lazy_import(self):
+        """Wenn der Client schon im Konstruktor da ist, wird _get_client
+        ihn direkt zurueckgeben — kein openai-Import."""
+        from app.adapters.qwen_bewerter import QwenBewerter
+        injected = object()
+        qb = QwenBewerter(client=injected)
+        assert qb._get_client() is injected