From e0a9de7fe3ef1cca52d602d3de030803cb94a29d Mon Sep 17 00:00:00 2001
From: Elias Meire <elias@meire.dev>
Date: Fri, 26 Sep 2025 14:47:37 +0200
Subject: [PATCH] fix(MCP Client Tool Node): Change default transport to HTTP
 Streamable (#20053)

Co-authored-by: Michael Kret <michael.k@radency.com>
---
 .../mcp/McpClientTool/McpClientTool.node.ts   | 33 ++++++++-----------
 .../nodes/mcp/McpClientTool/descriptions.ts   | 26 +++++++++++++++
 2 files changed, 40 insertions(+), 19 deletions(-)
 create mode 100644 packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/descriptions.ts

diff --git a/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/McpClientTool.node.ts b/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/McpClientTool.node.ts
index 3167c400fbe..8cc5546c6f8 100644
--- a/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/McpClientTool.node.ts
+++ b/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/McpClientTool.node.ts
@@ -9,6 +9,7 @@ import {
 	type SupplyData,
 } from 'n8n-workflow';
 
+import { transportSelect } from './descriptions';
 import { getTools } from './loadOptions';
 import type { McpServerTransport, McpAuthenticationOption, McpToolIncludeMode } from './types';
 import {
@@ -30,7 +31,7 @@ export class McpClientTool implements INodeType {
 			dark: 'file:../mcp.dark.svg',
 		},
 		group: ['output'],
-		version: [1, 1.1],
+		version: [1, 1.1, 1.2],
 		description: 'Connect tools from an MCP Server',
 		defaults: {
 			name: 'MCP Client',
@@ -102,28 +103,22 @@ export class McpClientTool implements INodeType {
 					},
 				},
 			},
-			{
-				displayName: 'Server Transport',
-				name: 'serverTransport',
-				type: 'options',
-				options: [
-					{
-						name: 'Server Sent Events (Deprecated)',
-						value: 'sse',
-					},
-					{
-						name: 'HTTP Streamable',
-						value: 'httpStreamable',
-					},
-				],
-				default: 'sse',
-				description: 'The transport used by your endpoint',
+			transportSelect({
+				defaultOption: 'sse',
 				displayOptions: {
 					show: {
-						'@version': [{ _cnd: { gte: 1.1 } }],
+						'@version': [1.1],
 					},
 				},
-			},
+			}),
+			transportSelect({
+				defaultOption: 'httpStreamable',
+				displayOptions: {
+					show: {
+						'@version': [{ _cnd: { gte: 1.2 } }],
+					},
+				},
+			}),
 			{
 				displayName: 'Authentication',
 				name: 'authentication',
diff --git a/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/descriptions.ts b/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/descriptions.ts
new file mode 100644
index 00000000000..089d4c40138
--- /dev/null
+++ b/packages/@n8n/nodes-langchain/nodes/mcp/McpClientTool/descriptions.ts
@@ -0,0 +1,26 @@
+import type { IDisplayOptions, INodeProperties } from 'n8n-workflow';
+
+export const transportSelect = ({
+	defaultOption,
+	displayOptions,
+}: {
+	defaultOption: 'sse' | 'httpStreamable';
+	displayOptions: IDisplayOptions;
+}): INodeProperties => ({
+	displayName: 'Server Transport',
+	name: 'serverTransport',
+	type: 'options',
+	options: [
+		{
+			name: 'HTTP Streamable',
+			value: 'httpStreamable',
+		},
+		{
+			name: 'Server Sent Events (Deprecated)',
+			value: 'sse',
+		},
+	],
+	default: defaultOption,
+	description: 'The transport used by your endpoint',
+	displayOptions,
+});