n8n MCP Server

Instructions

Implementation Reference

• src/index.ts:1790-1820 (handler)

  The main handler for the 'update-tag' tool within the CallToolRequestSchema switch statement. It retrieves the N8nClient instance and calls its updateTag method.
  case "update-tag": { const { clientId, id, name } = args as { clientId: string; id: string; name: string }; const client = clients.get(clientId); if (!client) { return { content: [{ type: "text", text: "Client not initialized. Please run init-n8n first.", }], isError: true }; } try { const tag = await client.updateTag(id, name); return { content: [{ type: "text", text: `Successfully updated tag:\n${JSON.stringify(tag, null, 2)}`, }] }; } catch (error) { return { content: [{ type: "text", text: error instanceof Error ? error.message : "Unknown error occurred", }], isError: true }; } }
• src/index.ts:317-322 (helper)

  The N8nClient method that performs the actual API call to update a tag's name via PUT /tags/{id}.
  async updateTag(id: string, name: string): Promise<N8nTag> { return this.makeRequest<N8nTag>(`/tags/${id}`, { method: 'PUT', body: JSON.stringify({ name }), }); }
• src/index.ts:770-782 (registration)

  Tool registration in the listTools response, including name, description, and input schema.
  { name: "update-tag", description: "Update a tag's name.", inputSchema: { type: "object", properties: { clientId: { type: "string" }, id: { type: "string" }, name: { type: "string" } }, required: ["clientId", "id", "name"] } },
• src/index.ts:80-322 (schema)

  Type definition for N8nTag used in updateTag responses.
  id: string; name: string; createdAt?: string; updatedAt?: string; } interface N8nTagList { data: N8nTag[]; nextCursor?: string; } interface N8nAuditResult { 'Credentials Risk Report'?: any; 'Database Risk Report'?: any; 'Filesystem Risk Report'?: any; 'Nodes Risk Report'?: any; 'Instance Risk Report'?: any; } class N8nClient { constructor( private baseUrl: string, private apiKey: string ) { // Remove trailing slash if present this.baseUrl = baseUrl.replace(/\/$/, ''); } private async makeRequest<T>(endpoint: string, options: any = {}): Promise<T> { const url = `${this.baseUrl}/api/v1${endpoint}`; const headers = { 'X-N8N-API-KEY': this.apiKey, 'Accept': 'application/json', 'Content-Type': 'application/json', }; try { const response = await fetch(url, { ...options, headers: { ...headers, ...options.headers, }, }); if (!response.ok) { const errorText = await response.text(); let errorMessage: string; try { const errorJson = JSON.parse(errorText); // Check for license-related errors if (errorJson.message && errorJson.message.includes('license')) { errorMessage = `This operation requires an n8n Enterprise license with project management features enabled. Error: ${errorJson.message}`; } else { errorMessage = errorJson.message || errorText; } } catch { errorMessage = errorText; } throw new Error(`N8N API error: ${errorMessage}`); } // Handle 204 No Content responses if (response.status === 204) { return {} as T; } return await response.json() as T; } catch (error) { if (error instanceof Error) { throw new Error(`Failed to connect to n8n: ${error.message}`); } throw error; } } async listWorkflows(): Promise<N8nWorkflowList> { return this.makeRequest<N8nWorkflowList>('/workflows'); } async getWorkflow(id: string): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>(`/workflows/${id}`); } async createWorkflow(name: string, nodes: any[] = [], connections: any = {}): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>('/workflows', { method: 'POST', body: JSON.stringify({ name, nodes, connections, settings: { saveManualExecutions: true, saveExecutionProgress: true, }, }), }); } async updateWorkflow(id: string, workflow: Partial<N8nWorkflow>): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>(`/workflows/${id}`, { method: 'PUT', body: JSON.stringify(workflow), }); } async deleteWorkflow(id: string): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>(`/workflows/${id}`, { method: 'DELETE', }); } async activateWorkflow(id: string): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>(`/workflows/${id}/activate`, { method: 'POST', }); } async deactivateWorkflow(id: string): Promise<N8nWorkflow> { return this.makeRequest<N8nWorkflow>(`/workflows/${id}/deactivate`, { method: 'POST', }); } // Project management methods (requires n8n Enterprise license) async listProjects(): Promise<N8nProjectList> { return this.makeRequest<N8nProjectList>('/projects'); } async createProject(name: string): Promise<void> { return this.makeRequest<void>('/projects', { method: 'POST', body: JSON.stringify({ name }), }); } async deleteProject(projectId: string): Promise<void> { return this.makeRequest<void>(`/projects/${projectId}`, { method: 'DELETE', }); } async updateProject(projectId: string, name: string): Promise<void> { return this.makeRequest<void>(`/projects/${projectId}`, { method: 'PUT', body: JSON.stringify({ name }), }); } // User management methods async listUsers(): Promise<N8nUserList> { return this.makeRequest<N8nUserList>('/users'); } async createUsers(users: Array<{ email: string; role?: 'global:admin' | 'global:member' }>): Promise<any> { return this.makeRequest('/users', { method: 'POST', body: JSON.stringify(users), }); } async getUser(idOrEmail: string): Promise<N8nUser> { return this.makeRequest<N8nUser>(`/users/${idOrEmail}`); } async deleteUser(idOrEmail: string): Promise<void> { return this.makeRequest<void>(`/users/${idOrEmail}`, { method: 'DELETE', }); } // Variable management methods async listVariables(): Promise<N8nVariableList> { return this.makeRequest<N8nVariableList>('/variables'); } async createVariable(key: string, value: string): Promise<void> { return this.makeRequest<void>('/variables', { method: 'POST', body: JSON.stringify({ key, value }), }); } async deleteVariable(id: string): Promise<void> { return this.makeRequest<void>(`/variables/${id}`, { method: 'DELETE', }); } // Execution management methods async getExecutions(options: { includeData?: boolean; status?: 'error' | 'success' | 'waiting'; workflowId?: string; limit?: number; } = {}): Promise<N8nExecutionList> { const params = new URLSearchParams(); if (options.includeData !== undefined) params.append('includeData', String(options.includeData)); if (options.status) params.append('status', options.status); if (options.workflowId) params.append('workflowId', options.workflowId); if (options.limit) params.append('limit', String(options.limit)); return this.makeRequest<N8nExecutionList>(`/executions?${params.toString()}`); } async getExecution(id: number, includeData: boolean = false): Promise<N8nExecution> { const params = new URLSearchParams(); if (includeData) params.append('includeData', 'true'); return this.makeRequest<N8nExecution>(`/executions/${id}?${params.toString()}`); } async deleteExecution(id: number): Promise<N8nExecution> { return this.makeRequest<N8nExecution>(`/executions/${id}`, { method: 'DELETE', }); } // Tag management methods async createTag(name: string): Promise<N8nTag> { return this.makeRequest<N8nTag>('/tags', { method: 'POST', body: JSON.stringify({ name }), }); } async getTags(options: { limit?: number } = {}): Promise<N8nTagList> { const params = new URLSearchParams(); if (options.limit) params.append('limit', String(options.limit)); return this.makeRequest<N8nTagList>(`/tags?${params.toString()}`); } async getTag(id: string): Promise<N8nTag> { return this.makeRequest<N8nTag>(`/tags/${id}`); } async updateTag(id: string, name: string): Promise<N8nTag> { return this.makeRequest<N8nTag>(`/tags/${id}`, { method: 'PUT', body: JSON.stringify({ name }), }); }