fix(auto-repair): preserve exact playbook candidates

apps/api/tests/test_playbook_service.py

@@ -25,6 +25,7 @@ from src.models.playbook import (
     RiskLevel,
     SymptomPattern,
 )
+from src.services.playbook_rag import PlaybookMatch
 from src.services.playbook_service import PlaybookService
 from src.utils.timezone import now_taipei
 
@@ -282,6 +283,92 @@ class TestPlaybookService:
         # Should be empty or have very low similarity
         assert len(recommendations) == 0 or recommendations[0].similarity_score < 0.4
 
+    @pytest.mark.asyncio
+    async def test_get_recommendations_prioritizes_exact_alert(self, service, mock_repo):
+        """Exact alert matches should win over fuzzy service matches."""
+        exact_alert = create_test_playbook(
+            playbook_id="PB-EXACT-ALERT",
+            success_count=0,
+            failure_count=0,
+        )
+        exact_alert.symptom_pattern.alert_names = ["AwoooPT16E"]
+        exact_alert.symptom_pattern.affected_services = ["different-service"]
+        competing_service = create_test_playbook(
+            playbook_id="PB-FUZZY-SERVICE",
+            success_count=20,
+            failure_count=0,
+        )
+        competing_service.symptom_pattern.alert_names = ["SentryDown"]
+        competing_service.symptom_pattern.affected_services = [
+            "awoooi-auto-repair-canary-livefire"
+        ]
+        await mock_repo.create(exact_alert)
+        await mock_repo.create(competing_service)
+
+        symptoms = SymptomPattern(
+            alert_names=["AwoooPT16E"],
+            affected_services=["awoooi-auto-repair-canary-livefire"],
+            severity_range=["P2"],
+        )
+
+        recommendations = await service.get_recommendations(
+            symptoms,
+            top_k=1,
+            use_rag=False,
+        )
+
+        assert recommendations[0].playbook.playbook_id == "PB-EXACT-ALERT"
+
+    @pytest.mark.asyncio
+    async def test_get_recommendations_preserves_jaccard_candidates(
+        self,
+        service,
+        mock_repo,
+    ):
+        """RAG hybrid top-k must not drop exact Jaccard candidates."""
+        exact_alert = create_test_playbook(
+            playbook_id="PB-EXACT-JACCARD",
+            success_count=0,
+            failure_count=0,
+        )
+        exact_alert.symptom_pattern.alert_names = ["AwoooPT16F"]
+        exact_alert.symptom_pattern.affected_services = ["different-service"]
+        competing_vector = create_test_playbook(
+            playbook_id="PB-VECTOR-ONLY",
+            success_count=20,
+            failure_count=0,
+        )
+        competing_vector.symptom_pattern.alert_names = ["SentryDown"]
+        competing_vector.symptom_pattern.affected_services = [
+            "awoooi-auto-repair-canary-livefire"
+        ]
+        await mock_repo.create(exact_alert)
+        await mock_repo.create(competing_vector)
+
+        class FakeRagService:
+            async def hybrid_search(self, **_kwargs):
+                return [
+                    PlaybookMatch(
+                        playbook_id="PB-VECTOR-ONLY",
+                        similarity_score=0.99,
+                        match_type="vector",
+                    )
+                ]
+
+        async def fake_rag_service():
+            return FakeRagService()
+
+        service._get_rag_service = fake_rag_service
+        symptoms = SymptomPattern(
+            alert_names=["AwoooPT16F"],
+            affected_services=["awoooi-auto-repair-canary-livefire"],
+            severity_range=["P2"],
+        )
+
+        recommendations = await service.get_recommendations(symptoms, top_k=1)
+
+        assert recommendations[0].playbook.playbook_id == "PB-EXACT-JACCARD"
+
     @pytest.mark.asyncio
     async def test_approve_playbook(self, service, mock_repo):
         """Test approving a draft playbook"""