diff --git a/src/services/workflow-validator.ts b/src/services/workflow-validator.ts
index 5dfdaef..f6d6552 100644
--- a/src/services/workflow-validator.ts
+++ b/src/services/workflow-validator.ts
@@ -399,6 +399,13 @@ export class WorkflowValidator {
         const nodeInfo = this.nodeRepository.getNode(normalizedType);
 
         if (!nodeInfo) {
+          // Skip validation for langchain nodes - they're validated by AI-specific validators
+          // This prevents database dependency issues while still ensuring proper validation
+          if (normalizedType.startsWith('nodes-langchain.')) {
+            // Langchain nodes are validated separately by validateAISpecificNodes()
+            continue;
+          }
+
           // Use NodeSimilarityService to find suggestions
           const suggestions = await this.similarityService.findSimilarNodes(node.type, 3);