diff --git a/docs b/docs
index 9526a7c..f657db0 160000
--- a/docs
+++ b/docs
@@ -1 +1 @@
-Subproject commit 9526a7c086aa795114f042181b2c87b90d67eb11
+Subproject commit f657db05336f7649b894b7f0b4e10807c7dcdf7a
diff --git a/internal/ai/rag/index.go b/internal/ai/rag/index.go
index 2816199..4f30185 100644
--- a/internal/ai/rag/index.go
+++ b/internal/ai/rag/index.go
@@ -119,33 +119,24 @@ func (s *index) IndexFAQByID(ctx context.Context, faqID int64) error {
 }
 
 func (s *index) RemoveDocumentIndex(ctx context.Context, documentID int64) error {
-	document := repositories.KnowledgeDocumentRepository.Get(sqls.DB(), documentID)
-	if document == nil {
-		return nil
-	}
 	chunks := repositories.KnowledgeChunkRepository.Find(sqls.DB(), sqls.NewCnd().Eq("document_id", documentID))
-	return s.removeDocumentIndexByChunks(ctx, document.KnowledgeBaseID, documentID, chunks)
+	return s.removeDocumentIndexByChunks(ctx, documentID, chunks)
 }
 
-func (s *index) RemoveDocumentIndexFromKnowledgeBase(ctx context.Context, knowledgeBaseID int64, documentID int64) error {
-	chunks := repositories.KnowledgeChunkRepository.Find(sqls.DB(), sqls.NewCnd().Eq("document_id", documentID))
-	return s.removeDocumentIndexByChunks(ctx, knowledgeBaseID, documentID, chunks)
+func (s *index) RemoveDocumentIndexByChunkModels(ctx context.Context, documentID int64, chunks []models.KnowledgeChunk) error {
+	return s.removeDocumentIndexByChunks(ctx, documentID, chunks)
 }
 
-func (s *index) RemoveDocumentIndexByChunkModels(ctx context.Context, knowledgeBaseID int64, documentID int64, chunks []models.KnowledgeChunk) error {
-	return s.removeDocumentIndexByChunks(ctx, knowledgeBaseID, documentID, chunks)
-}
-
-func (s *index) removeDocumentIndexByChunks(ctx context.Context, knowledgeBaseID int64, documentID int64, chunks []models.KnowledgeChunk) error {
+func (s *index) removeDocumentIndexByChunks(ctx context.Context, documentID int64, chunks []models.KnowledgeChunk) error {
 	if len(chunks) == 0 {
 		return nil
 	}
 
-	if err := s.deleteChunkVectors(ctx, collectChunkVectorIDs(chunks)); err != nil {
+	if err := s.deleteChunkVectors(ctx, s.collectChunkVectorIDs(chunks)); err != nil {
 		slog.Error("Failed to delete vectors", "error", err)
 	}
 
-	if err := deleteChunksByCondition("document_id", documentID); err != nil {
+	if err := repositories.KnowledgeChunkRepository.DeleteByDocumentID(sqls.DB(), documentID); err != nil {
 		return fmt.Errorf("failed to delete chunks: %w", err)
 	}
 
@@ -154,26 +145,36 @@ func (s *index) removeDocumentIndexByChunks(ctx context.Context, knowledgeBaseID
 }
 
 func (s *index) RemoveFAQIndex(ctx context.Context, faqID int64) error {
-	faq := repositories.KnowledgeFAQRepository.Get(sqls.DB(), faqID)
-	if faq == nil {
-		return nil
-	}
 	chunks := repositories.KnowledgeChunkRepository.FindByFaqID(sqls.DB(), faqID)
-	return s.removeFAQIndexByChunks(ctx, faq.KnowledgeBaseID, faqID, chunks)
+	return s.removeFAQIndexByChunks(ctx, faqID, chunks)
 }
 
-func (s *index) RemoveFAQIndexByChunkModels(ctx context.Context, knowledgeBaseID int64, faqID int64, chunks []models.KnowledgeChunk) error {
-	return s.removeFAQIndexByChunks(ctx, knowledgeBaseID, faqID, chunks)
+func (s *index) RemoveFAQIndexByChunkModels(ctx context.Context, faqID int64, chunks []models.KnowledgeChunk) error {
+	return s.removeFAQIndexByChunks(ctx, faqID, chunks)
 }
 
-func (s *index) removeFAQIndexByChunks(ctx context.Context, knowledgeBaseID int64, faqID int64, chunks []models.KnowledgeChunk) error {
+func (s *index) RemoveKnowledgeBaseIndexByChunkModels(ctx context.Context, knowledgeBaseID int64, chunks []models.KnowledgeChunk) error {
 	if len(chunks) == 0 {
 		return nil
 	}
-	if err := s.deleteChunkVectors(ctx, collectChunkVectorIDs(chunks)); err != nil {
+	if err := s.deleteChunkVectors(ctx, s.collectChunkVectorIDs(chunks)); err != nil {
+		return fmt.Errorf("failed to delete vectors for knowledge base %d: %w", knowledgeBaseID, err)
+	}
+	if err := repositories.KnowledgeChunkRepository.DeleteByKnowledgeBaseID(sqls.DB(), knowledgeBaseID); err != nil {
+		return fmt.Errorf("failed to delete chunks for knowledge base %d: %w", knowledgeBaseID, err)
+	}
+	slog.Info("Knowledge base index removed", "knowledge_base_id", knowledgeBaseID, "chunks_removed", len(chunks))
+	return nil
+}
+
+func (s *index) removeFAQIndexByChunks(ctx context.Context, faqID int64, chunks []models.KnowledgeChunk) error {
+	if len(chunks) == 0 {
+		return nil
+	}
+	if err := s.deleteChunkVectors(ctx, s.collectChunkVectorIDs(chunks)); err != nil {
 		slog.Error("Failed to delete faq vectors", "error", err)
 	}
-	if err := deleteChunksByCondition("faq_id", faqID); err != nil {
+	if err := repositories.KnowledgeChunkRepository.DeleteByFaqID(sqls.DB(), faqID); err != nil {
 		return fmt.Errorf("failed to delete faq chunks: %w", err)
 	}
 	slog.Info("FAQ index removed", "faq_id", faqID, "chunks_removed", len(chunks))
diff --git a/internal/ai/rag/index_cleanup_helpers.go b/internal/ai/rag/index_cleanup_helpers.go
index d043009..89c57a1 100644
--- a/internal/ai/rag/index_cleanup_helpers.go
+++ b/internal/ai/rag/index_cleanup_helpers.go
@@ -7,12 +7,13 @@ import (
 
 	"agent-desk/internal/ai/rag/vectordb"
 	"agent-desk/internal/models"
+	"agent-desk/internal/repositories"
 
 	"github.com/mlogclub/simple/common/strs"
 	"github.com/mlogclub/simple/sqls"
 )
 
-func collectChunkVectorIDs(chunks []models.KnowledgeChunk) []string {
+func (s *index) collectChunkVectorIDs(chunks []models.KnowledgeChunk) []string {
 	vectorIDs := make([]string, 0, len(chunks))
 	for _, chunk := range chunks {
 		if strs.IsNotBlank(chunk.VectorID) {
@@ -33,18 +34,12 @@ func (s *index) deleteChunkVectors(ctx context.Context, vectorIDs []string) erro
 	return provider.DeleteVectors(ctx, s.getCollectionName(), vectorIDs)
 }
 
-func deleteChunksByCondition(column string, value int64) error {
-	return sqls.WithTransaction(func(ctx *sqls.TxContext) error {
-		return ctx.Tx.Where(column+" = ?", value).Delete(&models.KnowledgeChunk{}).Error
-	})
-}
-
 func (s *index) cleanupKnowledgeBaseChunks(ctx context.Context, knowledgeBaseID int64, chunks []models.KnowledgeChunk) error {
-	vectorIDs := collectChunkVectorIDs(chunks)
+	vectorIDs := s.collectChunkVectorIDs(chunks)
 	if err := s.deleteChunkVectors(ctx, vectorIDs); err != nil {
 		return fmt.Errorf("failed to delete vectors for knowledge base %d before rebuild: %w", knowledgeBaseID, err)
 	}
-	if err := deleteChunksByCondition("knowledge_base_id", knowledgeBaseID); err != nil {
+	if err := repositories.KnowledgeChunkRepository.DeleteByKnowledgeBaseID(sqls.DB(), knowledgeBaseID); err != nil {
 		return fmt.Errorf("failed to clear chunks before rebuild: %w", err)
 	}
 	slog.Info("Knowledge base index storage reset",
diff --git a/internal/ai/rag/index_document_helpers.go b/internal/ai/rag/index_document_helpers.go
index 3b39a3e..0e7d108 100644
--- a/internal/ai/rag/index_document_helpers.go
+++ b/internal/ai/rag/index_document_helpers.go
@@ -45,7 +45,7 @@ func (s *index) buildDocumentChunks(ctx context.Context, document models.Knowled
 	return chunks, nil
 }
 
-func collectExistingVectorIDs(chunks []models.KnowledgeChunk) []string {
+func (s *index) collectExistingVectorIDs(chunks []models.KnowledgeChunk) []string {
 	ret := make([]string, 0, len(chunks))
 	for _, chunk := range chunks {
 		if strs.IsNotBlank(chunk.VectorID) {
diff --git a/internal/ai/rag/index_run_helpers.go b/internal/ai/rag/index_run_helpers.go
index 1992fa7..67aa09d 100644
--- a/internal/ai/rag/index_run_helpers.go
+++ b/internal/ai/rag/index_run_helpers.go
@@ -29,7 +29,7 @@ func (s *index) runDocumentIndex(ctx context.Context, document models.KnowledgeD
 		return nil, 0, fmt.Errorf("failed to get embedding model: %w", err)
 	}
 
-	existingVectorIDs := collectExistingVectorIDs(existingChunks)
+	existingVectorIDs := s.collectExistingVectorIDs(existingChunks)
 	vectors, chunkModels, dimension, err := s.prepareDocumentVectors(ctx, knowledgeBase, document, chunks)
 	if err != nil {
 		return nil, 0, err
diff --git a/internal/repositories/ai_agent_repository.go b/internal/repositories/ai_agent_repository.go
index a38ad8c..165b047 100644
--- a/internal/repositories/ai_agent_repository.go
+++ b/internal/repositories/ai_agent_repository.go
@@ -1,7 +1,10 @@
 package repositories
 
 import (
+	"strconv"
+
 	"agent-desk/internal/models"
+	"agent-desk/internal/pkg/enums"
 
 	"agent-desk/internal/pkg/httpx/params"
 
@@ -109,3 +112,16 @@ func (r *aIAgentRepository) FindByIds(db *gorm.DB, ids []int64) []models.AIAgent
 	db.Where("id IN ?", ids).Find(&list)
 	return list
 }
+
+func (r *aIAgentRepository) FindByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) (list []models.AIAgent) {
+	id := strconv.FormatInt(knowledgeBaseID, 10)
+	db.Where(
+		"(knowledge_ids = ? OR knowledge_ids LIKE ? OR knowledge_ids LIKE ? OR knowledge_ids LIKE ?) AND status <> ?",
+		id,
+		id+",%",
+		"%,"+id,
+		"%,"+id+",%",
+		enums.StatusDeleted,
+	).Find(&list)
+	return
+}
diff --git a/internal/repositories/knowledge_chunk_repository.go b/internal/repositories/knowledge_chunk_repository.go
index c19e457..566a527 100644
--- a/internal/repositories/knowledge_chunk_repository.go
+++ b/internal/repositories/knowledge_chunk_repository.go
@@ -96,12 +96,16 @@ func (r *knowledgeChunkRepository) Delete(db *gorm.DB, id int64) {
 	db.Delete(&models.KnowledgeChunk{}, "id = ?", id)
 }
 
-func (r *knowledgeChunkRepository) DeleteByDocumentID(db *gorm.DB, documentID int64) {
-	db.Delete(&models.KnowledgeChunk{}, "document_id = ?", documentID)
+func (r *knowledgeChunkRepository) DeleteByDocumentID(db *gorm.DB, documentID int64) error {
+	return db.Delete(&models.KnowledgeChunk{}, "document_id = ?", documentID).Error
 }
 
-func (r *knowledgeChunkRepository) DeleteByFaqID(db *gorm.DB, faqID int64) {
-	db.Delete(&models.KnowledgeChunk{}, "faq_id = ?", faqID)
+func (r *knowledgeChunkRepository) DeleteByFaqID(db *gorm.DB, faqID int64) error {
+	return db.Delete(&models.KnowledgeChunk{}, "faq_id = ?", faqID).Error
+}
+
+func (r *knowledgeChunkRepository) DeleteByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) error {
+	return db.Delete(&models.KnowledgeChunk{}, "knowledge_base_id = ?", knowledgeBaseID).Error
 }
 
 func (r *knowledgeChunkRepository) FindByDocumentID(db *gorm.DB, documentID int64) (list []models.KnowledgeChunk) {
diff --git a/internal/repositories/knowledge_document_repository.go b/internal/repositories/knowledge_document_repository.go
index 9e0517b..922254c 100644
--- a/internal/repositories/knowledge_document_repository.go
+++ b/internal/repositories/knowledge_document_repository.go
@@ -2,6 +2,7 @@ package repositories
 
 import (
 	"agent-desk/internal/models"
+	"agent-desk/internal/pkg/enums"
 
 	"agent-desk/internal/pkg/httpx/params"
 
@@ -103,6 +104,10 @@ func (r *knowledgeDocumentRepository) Delete(db *gorm.DB, id int64) {
 	db.Delete(&models.KnowledgeDocument{}, "id = ?", id)
 }
 
+func (r *knowledgeDocumentRepository) DeleteByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) error {
+	return db.Delete(&models.KnowledgeDocument{}, "knowledge_base_id = ?", knowledgeBaseID).Error
+}
+
 func (r *knowledgeDocumentRepository) FindByIDs(db *gorm.DB, ids []int64) (list []models.KnowledgeDocument) {
 	if len(ids) == 0 {
 		return nil
@@ -113,6 +118,6 @@ func (r *knowledgeDocumentRepository) FindByIDs(db *gorm.DB, ids []int64) (list
 
 func (r *knowledgeDocumentRepository) CountByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) int64 {
 	var count int64
-	db.Model(&models.KnowledgeDocument{}).Where("knowledge_base_id = ?", knowledgeBaseID).Count(&count)
+	db.Model(&models.KnowledgeDocument{}).Where("knowledge_base_id = ? AND status <> ?", knowledgeBaseID, enums.StatusDeleted).Count(&count)
 	return count
 }
diff --git a/internal/repositories/knowledge_faq_repository.go b/internal/repositories/knowledge_faq_repository.go
index b97513b..6c3fa00 100644
--- a/internal/repositories/knowledge_faq_repository.go
+++ b/internal/repositories/knowledge_faq_repository.go
@@ -58,6 +58,10 @@ func (r *knowledgeFAQRepository) Delete(db *gorm.DB, id int64) {
 	db.Delete(&models.KnowledgeFAQ{}, "id = ?", id)
 }
 
+func (r *knowledgeFAQRepository) DeleteByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) error {
+	return db.Delete(&models.KnowledgeFAQ{}, "knowledge_base_id = ?", knowledgeBaseID).Error
+}
+
 func (r *knowledgeFAQRepository) FindByIDs(db *gorm.DB, ids []int64) (list []models.KnowledgeFAQ) {
 	if len(ids) == 0 {
 		return nil
@@ -81,6 +85,6 @@ func (r *knowledgeFAQRepository) FindByKnowledgeBaseIDAndQuestions(db *gorm.DB,
 
 func (r *knowledgeFAQRepository) CountByKnowledgeBaseID(db *gorm.DB, knowledgeBaseID int64) int64 {
 	var count int64
-	db.Model(&models.KnowledgeFAQ{}).Where("knowledge_base_id = ?", knowledgeBaseID).Count(&count)
+	db.Model(&models.KnowledgeFAQ{}).Where("knowledge_base_id = ? AND status <> ?", knowledgeBaseID, enums.StatusDeleted).Count(&count)
 	return count
 }
diff --git a/internal/services/knowledge_base_service.go b/internal/services/knowledge_base_service.go
index e11c74f..90c6147 100644
--- a/internal/services/knowledge_base_service.go
+++ b/internal/services/knowledge_base_service.go
@@ -1,8 +1,11 @@
 package services
 
 import (
+	"context"
+	"fmt"
 	"time"
 
+	"agent-desk/internal/ai/rag"
 	"agent-desk/internal/models"
 	"agent-desk/internal/pkg/dto"
 	"agent-desk/internal/pkg/dto/request"
@@ -125,16 +128,32 @@ func (s *knowledgeBaseService) DeleteKnowledgeBase(id int64) error {
 	if current == nil {
 		return errorsx.InvalidParam("知识库不存在")
 	}
-	docCount := repositories.KnowledgeDocumentRepository.CountByKnowledgeBaseID(sqls.DB(), id)
-	if docCount > 0 {
-		return errorsx.InvalidParam("知识库下存在文档，无法删除")
+
+	referencingAgents := repositories.AIAgentRepository.FindByKnowledgeBaseID(sqls.DB(), id)
+	if len(referencingAgents) > 0 {
+		if len(referencingAgents) == 1 {
+			return errorsx.Forbidden(fmt.Sprintf("知识库已被 AI Agent「%s」引用，请先解除绑定", referencingAgents[0].Name))
+		}
+		return errorsx.Forbidden(fmt.Sprintf("知识库已被 %d 个 AI Agent 引用，请先解除绑定", len(referencingAgents)))
 	}
-	faqCount := repositories.KnowledgeFAQRepository.CountByKnowledgeBaseID(sqls.DB(), id)
-	if faqCount > 0 {
-		return errorsx.InvalidParam("知识库下存在FAQ，无法删除")
+
+	chunks := repositories.KnowledgeChunkRepository.Find(sqls.DB(), sqls.NewCnd().Eq("knowledge_base_id", id))
+	if err := sqls.WithTransaction(func(ctx *sqls.TxContext) error {
+		if err := repositories.KnowledgeChunkRepository.DeleteByKnowledgeBaseID(ctx.Tx, id); err != nil {
+			return err
+		}
+		if err := repositories.KnowledgeDocumentRepository.DeleteByKnowledgeBaseID(ctx.Tx, id); err != nil {
+			return err
+		}
+		if err := repositories.KnowledgeFAQRepository.DeleteByKnowledgeBaseID(ctx.Tx, id); err != nil {
+			return err
+		}
+		return ctx.Tx.Delete(&models.KnowledgeBase{}, "id = ?", id).Error
+	}); err != nil {
+		return err
 	}
-	repositories.KnowledgeBaseRepository.Delete(sqls.DB(), id)
-	return nil
+
+	return rag.Index.RemoveKnowledgeBaseIndexByChunkModels(context.Background(), id, chunks)
 }
 
 func (s *knowledgeBaseService) UpdateSort(ids []int64) error {
diff --git a/internal/services/knowledge_base_service_test.go b/internal/services/knowledge_base_service_test.go
index a601834..aa6b7b9 100644
--- a/internal/services/knowledge_base_service_test.go
+++ b/internal/services/knowledge_base_service_test.go
@@ -1,9 +1,18 @@
 package services
 
 import (
+	"fmt"
+	"strings"
 	"testing"
 
+	"agent-desk/internal/models"
 	"agent-desk/internal/pkg/dto/request"
+	"agent-desk/internal/pkg/enums"
+	"agent-desk/internal/repositories"
+
+	"github.com/glebarez/sqlite"
+	"github.com/mlogclub/simple/sqls"
+	"gorm.io/gorm"
 )
 
 func TestBuildKnowledgeBaseModelUsesLowerDefaultScoreThreshold(t *testing.T) {
@@ -15,3 +24,111 @@ func TestBuildKnowledgeBaseModelUsesLowerDefaultScoreThreshold(t *testing.T) {
 		t.Fatalf("expected default score threshold 0.2, got %v", item.DefaultScoreThreshold)
 	}
 }
+
+func TestDeleteKnowledgeBaseRejectsAIAgentReference(t *testing.T) {
+	setupKnowledgeBaseServiceTestDB(t)
+	kb := createKnowledgeBaseServiceTestBase(t, "Referenced KB")
+	otherKB := createKnowledgeBaseServiceTestBase(t, "Other KB")
+	if err := repositories.AIAgentRepository.Create(sqls.DB(), &models.AIAgent{
+		Name:         "Support Agent",
+		Status:       enums.StatusOk,
+		KnowledgeIDs: "12",
+	}); err != nil {
+		t.Fatalf("create unrelated ai agent: %v", err)
+	}
+	if err := repositories.AIAgentRepository.Create(sqls.DB(), &models.AIAgent{
+		Name:         "Knowledge Agent",
+		Status:       enums.StatusOk,
+		KnowledgeIDs: fmt.Sprintf("12,%d,%d", kb.ID, otherKB.ID),
+	}); err != nil {
+		t.Fatalf("create ai agent: %v", err)
+	}
+
+	err := KnowledgeBaseService.DeleteKnowledgeBase(kb.ID)
+	if err == nil {
+		t.Fatal("DeleteKnowledgeBase() error is nil, want referenced knowledge base error")
+	}
+	if got := err.Error(); !strings.Contains(got, "Knowledge Agent") {
+		t.Fatalf("DeleteKnowledgeBase() error = %q, want agent name", got)
+	}
+	if repositories.KnowledgeBaseRepository.Get(sqls.DB(), kb.ID) == nil {
+		t.Fatal("knowledge base was deleted despite ai agent reference")
+	}
+}
+
+func TestDeleteKnowledgeBaseCascadesContentWhenNotReferenced(t *testing.T) {
+	setupKnowledgeBaseServiceTestDB(t)
+	kb := createKnowledgeBaseServiceTestBase(t, "Delete KB")
+	document := &models.KnowledgeDocument{
+		KnowledgeBaseID: kb.ID,
+		Title:           "Doc",
+		ContentType:     enums.KnowledgeDocumentContentTypeMarkdown,
+		Content:         "content",
+		Status:          enums.StatusOk,
+		IndexStatus:     enums.KnowledgeDocumentIndexStatusIndexed,
+	}
+	if err := repositories.KnowledgeDocumentRepository.Create(sqls.DB(), document); err != nil {
+		t.Fatalf("create document: %v", err)
+	}
+	faq := &models.KnowledgeFAQ{
+		KnowledgeBaseID: kb.ID,
+		Question:        "Question",
+		Answer:          "Answer",
+		Status:          enums.StatusOk,
+		IndexStatus:     enums.KnowledgeDocumentIndexStatusIndexed,
+	}
+	if err := repositories.KnowledgeFAQRepository.Create(sqls.DB(), faq); err != nil {
+		t.Fatalf("create faq: %v", err)
+	}
+	if err := repositories.KnowledgeChunkRepository.BatchCreate(sqls.DB(), []models.KnowledgeChunk{
+		{KnowledgeBaseID: kb.ID, DocumentID: document.ID, ChunkNo: 1, Status: enums.StatusOk},
+		{KnowledgeBaseID: kb.ID, FaqID: faq.ID, ChunkNo: 1, Status: enums.StatusOk},
+	}); err != nil {
+		t.Fatalf("create chunks: %v", err)
+	}
+
+	if err := KnowledgeBaseService.DeleteKnowledgeBase(kb.ID); err != nil {
+		t.Fatalf("DeleteKnowledgeBase() error = %v", err)
+	}
+
+	assertKnowledgeBaseServiceTestCount(t, &models.KnowledgeBase{}, "id = ?", kb.ID, 0)
+	assertKnowledgeBaseServiceTestCount(t, &models.KnowledgeDocument{}, "knowledge_base_id = ?", kb.ID, 0)
+	assertKnowledgeBaseServiceTestCount(t, &models.KnowledgeFAQ{}, "knowledge_base_id = ?", kb.ID, 0)
+	assertKnowledgeBaseServiceTestCount(t, &models.KnowledgeChunk{}, "knowledge_base_id = ?", kb.ID, 0)
+}
+
+func setupKnowledgeBaseServiceTestDB(t *testing.T) {
+	t.Helper()
+	db, err := gorm.Open(sqlite.Open("file:"+t.Name()+"?mode=memory&cache=shared"), &gorm.Config{})
+	if err != nil {
+		t.Fatalf("open sqlite db: %v", err)
+	}
+	if err := db.AutoMigrate(&models.KnowledgeBase{}, &models.KnowledgeDocument{}, &models.KnowledgeFAQ{}, &models.KnowledgeChunk{}, &models.AIAgent{}); err != nil {
+		t.Fatalf("auto migrate: %v", err)
+	}
+	sqls.SetDB(db)
+}
+
+func createKnowledgeBaseServiceTestBase(t *testing.T, name string) *models.KnowledgeBase {
+	t.Helper()
+	item := &models.KnowledgeBase{
+		Name:          name,
+		KnowledgeType: string(enums.KnowledgeBaseTypeDocument),
+		Status:        enums.StatusOk,
+	}
+	if err := repositories.KnowledgeBaseRepository.Create(sqls.DB(), item); err != nil {
+		t.Fatalf("create knowledge base: %v", err)
+	}
+	return item
+}
+
+func assertKnowledgeBaseServiceTestCount(t *testing.T, model any, query string, arg any, want int64) {
+	t.Helper()
+	var count int64
+	if err := sqls.DB().Model(model).Where(query, arg).Count(&count).Error; err != nil {
+		t.Fatalf("count %T: %v", model, err)
+	}
+	if count != want {
+		t.Fatalf("count %T = %d, want %d", model, count, want)
+	}
+}
diff --git a/internal/services/knowledge_document_service.go b/internal/services/knowledge_document_service.go
index 2a5fbcb..2dea773 100644
--- a/internal/services/knowledge_document_service.go
+++ b/internal/services/knowledge_document_service.go
@@ -155,7 +155,7 @@ func (s *knowledgeDocumentService) UpdateKnowledgeDocument(req request.UpdateKno
 	}
 
 	if oldKnowledgeBaseID != item.KnowledgeBaseID {
-		if err := rag.Index.RemoveDocumentIndexFromKnowledgeBase(context.Background(), oldKnowledgeBaseID, req.ID); err != nil {
+		if err := rag.Index.RemoveDocumentIndex(context.Background(), req.ID); err != nil {
 			slog.Error("failed to remove old document index after knowledge base change", "document_id", req.ID, "knowledge_base_id", oldKnowledgeBaseID, "error", err)
 		}
 	}
@@ -167,10 +167,6 @@ func (s *knowledgeDocumentService) UpdateKnowledgeDocument(req request.UpdateKno
 }
 
 func (s *knowledgeDocumentService) DeleteKnowledgeDocument(id int64) error {
-	current := s.Get(id)
-	if current == nil {
-		return errorsx.InvalidParam("文档不存在")
-	}
 	chunks := repositories.KnowledgeChunkRepository.FindByDocumentID(sqls.DB(), id)
 	if err := sqls.WithTransaction(func(ctx *sqls.TxContext) error {
 		_ = repositories.KnowledgeDocumentRepository.Updates(ctx.Tx, id, map[string]any{
@@ -182,7 +178,7 @@ func (s *knowledgeDocumentService) DeleteKnowledgeDocument(id int64) error {
 	}); err != nil {
 		return err
 	}
-	return rag.Index.RemoveDocumentIndexByChunkModels(context.Background(), current.KnowledgeBaseID, id, chunks)
+	return rag.Index.RemoveDocumentIndexByChunkModels(context.Background(), id, chunks)
 }
 
 func (s *knowledgeDocumentService) buildKnowledgeDocumentModel(req request.CreateKnowledgeDocumentRequest) (*models.KnowledgeDocument, error) {
diff --git a/internal/services/knowledge_faq_service.go b/internal/services/knowledge_faq_service.go
index d5c9ee2..bf6a073 100644
--- a/internal/services/knowledge_faq_service.go
+++ b/internal/services/knowledge_faq_service.go
@@ -113,7 +113,7 @@ func (s *knowledgeFAQService) DeleteKnowledgeFAQ(id int64) error {
 	}); err != nil {
 		return err
 	}
-	return rag.Index.RemoveFAQIndexByChunkModels(context.Background(), current.KnowledgeBaseID, id, chunks)
+	return rag.Index.RemoveFAQIndexByChunkModels(context.Background(), id, chunks)
 }
 
 func (s *knowledgeFAQService) buildKnowledgeFAQModel(req request.CreateKnowledgeFAQRequest) (*models.KnowledgeFAQ, error) {