feat(MCP Server Trigger Node): Add MCP Server Trigger node to expose tools to MCP clients (#14403)

Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>

packages/frontend/editor-ui/src/Interface.ts

@@ -954,6 +954,8 @@ export interface RootState {
 	endpointForm: string;
 	endpointFormTest: string;
 	endpointFormWaiting: string;
+	endpointMcp: string;
+	endpointMcpTest: string;
 	endpointWebhook: string;
 	endpointWebhookTest: string;
 	endpointWebhookWaiting: string;

packages/frontend/editor-ui/src/__tests__/defaults.ts

@@ -15,6 +15,8 @@ export const defaultSettings: FrontendSettings = {
 	endpointForm: '',
 	endpointFormTest: '',
 	endpointFormWaiting: '',
+	endpointMcp: '',
+	endpointMcpTest: '',
 	endpointWebhook: '',
 	endpointWebhookTest: '',
 	endpointWebhookWaiting: '',

packages/frontend/editor-ui/src/components/NodeWebhooks.vue

@@ -4,6 +4,7 @@ import { useToast } from '@/composables/useToast';
 import {
 	CHAT_TRIGGER_NODE_TYPE,
 	FORM_TRIGGER_NODE_TYPE,
+	MCP_TRIGGER_NODE_TYPE,
 	OPEN_URL_PANEL_TRIGGER_NODE_TYPES,
 	PRODUCTION_ONLY_TRIGGER_NODE_TYPES,
 } from '@/constants';
@@ -31,7 +32,7 @@ const isMinimized = ref(
 	props.nodeTypeDescription &&
 		!OPEN_URL_PANEL_TRIGGER_NODE_TYPES.includes(props.nodeTypeDescription.name),
 );
-const showUrlFor = ref('test');
+const showUrlFor = ref<'test' | 'production'>('test');
 
 const isProductionOnly = computed(() => {
 	return (
@@ -95,6 +96,18 @@ const baseText = computed(() => {
 				copyMessage: i18n.baseText('nodeWebhooks.showMessage.message.formTrigger'),
 			};
 
+		case MCP_TRIGGER_NODE_TYPE:
+			return {
+				toggleTitle: i18n.baseText('nodeWebhooks.webhookUrls.mcpTrigger'),
+				clickToDisplay: i18n.baseText('nodeWebhooks.clickToDisplayWebhookUrls.mcpTrigger'),
+				clickToHide: i18n.baseText('nodeWebhooks.clickToHideWebhookUrls.mcpTrigger'),
+				clickToCopy: i18n.baseText('nodeWebhooks.clickToCopyWebhookUrls.mcpTrigger'),
+				testUrl: i18n.baseText('nodeWebhooks.testUrl'),
+				productionUrl: i18n.baseText('nodeWebhooks.productionUrl'),
+				copyTitle: i18n.baseText('nodeWebhooks.showMessage.title.mcpTrigger'),
+				copyMessage: undefined,
+			};
+
 		default:
 			return {
 				toggleTitle: i18n.baseText('nodeWebhooks.webhookUrls'),

packages/frontend/editor-ui/src/composables/useCanvasOperations.ts

@@ -27,6 +27,7 @@ import { useWorkflowHelpers } from '@/composables/useWorkflowHelpers';
 import {
 	EnterpriseEditionFeature,
 	FORM_TRIGGER_NODE_TYPE,
+	MCP_TRIGGER_NODE_TYPE,
 	STICKY_NODE_TYPE,
 	UPDATE_WEBHOOK_ID_NODE_TYPES,
 	WEBHOOK_NODE_TYPE,
@@ -1071,7 +1072,7 @@ export function useCanvasOperations({ router }: { router: ReturnType<typeof useR
 
 		// if it's a webhook and the path is empty set the UUID as the default path
 		if (
-			[WEBHOOK_NODE_TYPE, FORM_TRIGGER_NODE_TYPE].includes(node.type) &&
+			[WEBHOOK_NODE_TYPE, FORM_TRIGGER_NODE_TYPE, MCP_TRIGGER_NODE_TYPE].includes(node.type) &&
 			node.parameters.path === ''
 		) {
 			node.parameters.path = node.webhookId as string;

packages/frontend/editor-ui/src/composables/useWorkflowHelpers.ts

@@ -679,20 +679,26 @@ export function useWorkflowHelpers(options: { router: ReturnType<typeof useRoute
 	function getWebhookUrl(
 		webhookData: IWebhookDescription,
 		node: INode,
-		showUrlFor?: string,
+		showUrlFor: 'test' | 'production',
 	): string {
-		const { isForm, restartWebhook } = webhookData;
+		const { nodeType, restartWebhook } = webhookData;
 		if (restartWebhook === true) {
-			return isForm ? '$execution.resumeFormUrl' : '$execution.resumeUrl';
-		}
-
-		let baseUrl;
-		if (showUrlFor === 'test') {
-			baseUrl = isForm ? rootStore.formTestUrl : rootStore.webhookTestUrl;
-		} else {
-			baseUrl = isForm ? rootStore.formUrl : rootStore.webhookUrl;
+			return nodeType === 'form' ? '$execution.resumeFormUrl' : '$execution.resumeUrl';
 		}
 
+		const baseUrls = {
+			test: {
+				form: rootStore.formTestUrl,
+				mcp: rootStore.mcpTestUrl,
+				webhook: rootStore.webhookTestUrl,
+			},
+			production: {
+				form: rootStore.formUrl,
+				mcp: rootStore.mcpUrl,
+				webhook: rootStore.webhookUrl,
+			},
+		} as const;
+		const baseUrl = baseUrls[showUrlFor][nodeType ?? 'webhook'];
 		const workflowId = workflowsStore.workflowId;
 		const path = getWebhookExpressionValue(webhookData, 'path', true, node.name) ?? '';
 		const isFullPath =

packages/frontend/editor-ui/src/constants.ts

@@ -143,6 +143,7 @@ export const JIRA_TRIGGER_NODE_TYPE = 'n8n-nodes-base.jiraTrigger';
 export const MICROSOFT_EXCEL_NODE_TYPE = 'n8n-nodes-base.microsoftExcel';
 export const MANUAL_TRIGGER_NODE_TYPE = 'n8n-nodes-base.manualTrigger';
 export const MANUAL_CHAT_TRIGGER_NODE_TYPE = '@n8n/n8n-nodes-langchain.manualChatTrigger';
+export const MCP_TRIGGER_NODE_TYPE = '@n8n/n8n-nodes-langchain.mcpTrigger';
 export const CHAT_TRIGGER_NODE_TYPE = '@n8n/n8n-nodes-langchain.chatTrigger';
 export const AGENT_NODE_TYPE = '@n8n/n8n-nodes-langchain.agent';
 export const OPEN_AI_NODE_TYPE = '@n8n/n8n-nodes-langchain.openAi';
@@ -239,6 +240,7 @@ export const OPEN_URL_PANEL_TRIGGER_NODE_TYPES = [
 	WEBHOOK_NODE_TYPE,
 	FORM_TRIGGER_NODE_TYPE,
 	CHAT_TRIGGER_NODE_TYPE,
+	MCP_TRIGGER_NODE_TYPE,
 ];
 
 export const SINGLE_WEBHOOK_TRIGGERS = [

packages/frontend/editor-ui/src/plugins/i18n/locales/en.json

@@ -1495,23 +1495,28 @@
 	"nodeWebhooks.clickToCopyWebhookUrls": "Click to copy webhook URLs",
 	"nodeWebhooks.clickToCopyWebhookUrls.formTrigger": "Click to copy Form URL",
 	"nodeWebhooks.clickToCopyWebhookUrls.chatTrigger": "Click to copy Chat URL",
+	"nodeWebhooks.clickToCopyWebhookUrls.mcpTrigger": "Click to copy MCP URL",
 	"nodeWebhooks.clickToDisplayWebhookUrls": "Click to display webhook URLs",
 	"nodeWebhooks.clickToDisplayWebhookUrls.formTrigger": "Click to display Form URL",
 	"nodeWebhooks.clickToDisplayWebhookUrls.chatTrigger": "Click to display Chat URL",
+	"nodeWebhooks.clickToDisplayWebhookUrls.mcpTrigger": "Click to display MCP URL",
 	"nodeWebhooks.clickToHideWebhookUrls": "Click to hide webhook URLs",
 	"nodeWebhooks.clickToHideWebhookUrls.formTrigger": "Click to hide Form URL",
 	"nodeWebhooks.clickToHideWebhookUrls.chatTrigger": "Click to hide Chat URL",
+	"nodeWebhooks.clickToHideWebhookUrls.mcpTrigger": "Click to hide MCP URL",
 	"nodeWebhooks.invalidExpression": "[INVALID EXPRESSION]",
 	"nodeWebhooks.productionUrl": "Production URL",
 	"nodeWebhooks.showMessage.title": "URL copied",
 	"nodeWebhooks.showMessage.title.formTrigger": "Form URL copied",
 	"nodeWebhooks.showMessage.title.chatTrigger": "Chat URL copied",
+	"nodeWebhooks.showMessage.title.mcpTrigger": "MCP URL copied",
 	"nodeWebhooks.showMessage.message.formTrigger": "Form submissions made via this URL will trigger the workflow when it's activated",
 	"nodeWebhooks.showMessage.message.chatTrigger": "Chat submissions made via this URL will trigger the workflow when it's activated",
 	"nodeWebhooks.testUrl": "Test URL",
 	"nodeWebhooks.webhookUrls": "Webhook URLs",
 	"nodeWebhooks.webhookUrls.formTrigger": "Form URLs",
 	"nodeWebhooks.webhookUrls.chatTrigger": "Chat URL",
+	"nodeWebhooks.webhookUrls.mcpTrigger": "MCP URL",
 	"openWorkflow.workflowImportError": "Could not import workflow",
 	"openWorkflow.workflowNotFoundError": "Could not find workflow",
 	"parameterInput.expressionResult": "e.g. {result}",

packages/frontend/editor-ui/src/stores/root.store.ts

@@ -7,7 +7,7 @@ import { computed, ref } from 'vue';
 const { VUE_APP_URL_BASE_API } = import.meta.env;
 
 export const useRootStore = defineStore(STORES.ROOT, () => {
-	const state = ref({
+	const state = ref<RootState>({
 		baseUrl: VUE_APP_URL_BASE_API ?? window.BASE_PATH,
 		restEndpoint:
 			!window.REST_ENDPOINT || window.REST_ENDPOINT === '{{REST_ENDPOINT}}'
@@ -17,6 +17,8 @@ export const useRootStore = defineStore(STORES.ROOT, () => {
 		endpointForm: 'form',
 		endpointFormTest: 'form-test',
 		endpointFormWaiting: 'form-waiting',
+		endpointMcp: 'mcp',
+		endpointMcpTest: 'mcp-test',
 		endpointWebhook: 'webhook',
 		endpointWebhookTest: 'webhook-test',
 		endpointWebhookWaiting: 'webhook-waiting',
@@ -49,10 +51,18 @@ export const useRootStore = defineStore(STORES.ROOT, () => {
 
 	const webhookUrl = computed(() => `${state.value.urlBaseWebhook}${state.value.endpointWebhook}`);
 
+	const webhookTestUrl = computed(
+		() => `${state.value.urlBaseEditor}${state.value.endpointWebhookTest}`,
+	);
+
 	const webhookWaitingUrl = computed(
 		() => `${state.value.urlBaseEditor}${state.value.endpointWebhookWaiting}`,
 	);
 
+	const mcpUrl = computed(() => `${state.value.urlBaseWebhook}${state.value.endpointMcp}`);
+
+	const mcpTestUrl = computed(() => `${state.value.urlBaseEditor}${state.value.endpointMcpTest}`);
+
 	const pushRef = computed(() => state.value.pushRef);
 
 	const binaryDataMode = computed(() => state.value.binaryDataMode);
@@ -67,10 +77,6 @@ export const useRootStore = defineStore(STORES.ROOT, () => {
 
 	const OAuthCallbackUrls = computed(() => state.value.oauthCallbackUrls);
 
-	const webhookTestUrl = computed(
-		() => `${state.value.urlBaseEditor}${state.value.endpointWebhookTest}`,
-	);
-
 	const restUrl = computed(() => `${state.value.baseUrl}${state.value.restEndpoint}`);
 
 	const executionTimeout = computed(() => state.value.executionTimeout);
@@ -164,7 +170,7 @@ export const useRootStore = defineStore(STORES.ROOT, () => {
 		state.value.defaultLocale = locale;
 	};
 
-	const setBinaryDataMode = (binaryDataMode: string) => {
+	const setBinaryDataMode = (binaryDataMode: RootState['binaryDataMode']) => {
 		state.value.binaryDataMode = binaryDataMode;
 	};
 
@@ -175,6 +181,8 @@ export const useRootStore = defineStore(STORES.ROOT, () => {
 		formUrl,
 		formTestUrl,
 		formWaitingUrl,
+		mcpUrl,
+		mcpTestUrl,
 		webhookUrl,
 		webhookTestUrl,
 		webhookWaitingUrl,