feat: add get_node_help tool to retrieve node documentation

README.md

@@ -1,6 +1,6 @@
 # Node-RED MCP Server
 
-MCP server for Node-RED workflow management. Provides AI assistants with 17 tools to manage flows, node modules, context stores, and runtime settings through the Node-RED Admin API v2.
+MCP server for Node-RED workflow management. Provides AI assistants with 18 tools to manage flows, node modules, context stores, and runtime settings through the Node-RED Admin API v2.
 
 ## Installation
 
@@ -131,6 +131,7 @@ Note: No `NODE_RED_TOKEN` needed - credentials are in the URL.
 
 ### Node Module Management
 - **get_nodes**: List all installed node modules with versions and status
+- **get_node_help**: Get the HTML help/documentation for a specific node type
 - **install_node**: Install a node module from the npm registry
 - **set_node_module_state**: Enable or disable an installed node module
 - **remove_node_module**: Uninstall a node module from Node-RED
@@ -171,6 +172,10 @@ Delete the flow with ID "flow1"
 What node modules are installed?
 ```
 
+```
+Show me the help docs for the zigbee2mqtt-in node
+```
+
 ```
 Install the node-red-contrib-mqtt module
 ```

src/client.ts

@@ -319,6 +319,25 @@ export class NodeRedClient {
     return z.array(NodeModuleSchema).parse(data);
   }
 
+  async getNodeHelp(module: string, set: string): Promise<string> {
+    const headers = this.getHeaders();
+    headers.Accept = 'text/html';
+    const response = await request(
+      `${this.baseUrl}/nodes/${encodeURIComponent(module)}/${encodeURIComponent(set)}`,
+      {
+        method: 'GET',
+        headers,
+      }
+    );
+
+    if (response.statusCode !== 200) {
+      const body = await response.body.text();
+      throw new Error(`Failed to get node help: ${response.statusCode}\n${body}`);
+    }
+
+    return await response.body.text();
+  }
+
   async installNode(module: string): Promise<NodeModule> {
     const response = await request(`${this.baseUrl}/nodes`, {
       method: 'POST',

src/server.ts

@@ -10,6 +10,7 @@ import { getContext } from './tools/get-context.js';
 import { getDiagnostics } from './tools/get-diagnostics.js';
 import { getFlowState } from './tools/get-flow-state.js';
 import { getFlows } from './tools/get-flows.js';
+import { getNodeHelp } from './tools/get-node-help.js';
 import { getNodes } from './tools/get-nodes.js';
 import { getSettings } from './tools/get-settings.js';
 import { installNode } from './tools/install-node.js';
@@ -214,6 +215,27 @@ export function createServer() {
           properties: {},
         },
       },
+      {
+        name: 'get_node_help',
+        description:
+          'Get the HTML help/documentation for a specific node type. Returns the same help content shown in the Node-RED editor info sidebar. Use get_nodes first to discover available module and set names.',
+        inputSchema: {
+          type: 'object',
+          properties: {
+            module: {
+              type: 'string',
+              description:
+                'Node module name (e.g. "node-red-contrib-zigbee2mqtt", "node-red")',
+            },
+            set: {
+              type: 'string',
+              description:
+                'Node set name within the module (e.g. "zigbee2mqtt-in", "inject")',
+            },
+          },
+          required: ['module', 'set'],
+        },
+      },
       {
         name: 'install_node',
         description: 'Install a new node module into Node-RED. Installs from the npm registry.',
@@ -339,6 +361,8 @@ export function createServer() {
           return await deleteContext(client, request.params.arguments);
         case 'get_nodes':
           return await getNodes(client);
+        case 'get_node_help':
+          return await getNodeHelp(client, request.params.arguments);
         case 'install_node':
           return await installNode(client, request.params.arguments);
         case 'set_node_module_state':

src/tools/get-node-help.ts

@@ -0,0 +1,20 @@
+import { z } from 'zod';
+import type { NodeRedClient } from '../client.js';
+
+const GetNodeHelpArgsSchema = z.object({
+  module: z.string(),
+  set: z.string(),
+});
+
+export async function getNodeHelp(client: NodeRedClient, args: unknown) {
+  const parsed = GetNodeHelpArgsSchema.parse(args);
+  const result = await client.getNodeHelp(parsed.module, parsed.set);
+  return {
+    content: [
+      {
+        type: 'text' as const,
+        text: result,
+      },
+    ],
+  };
+}

tests/client-runtime.test.ts

@@ -108,4 +108,65 @@ describe('NodeRedClient - Runtime Info', () => {
       expect(result).toEqual(diagnosticsWithExtras);
     });
   });
+
+  describe('getNodeHelp', () => {
+    it('should fetch node help HTML successfully', async () => {
+      const mockHtml = '<p>This node does something useful.</p>';
+
+      vi.mocked(request).mockResolvedValue({
+        statusCode: 200,
+        body: { text: vi.fn().mockResolvedValue(mockHtml) },
+      } as any);
+
+      const result = await client.getNodeHelp('node-red-contrib-zigbee2mqtt', 'zigbee2mqtt-in');
+      expect(result).toBe(mockHtml);
+      expect(request).toHaveBeenCalledWith(
+        'http://localhost:1880/nodes/node-red-contrib-zigbee2mqtt/zigbee2mqtt-in',
+        {
+          method: 'GET',
+          headers: {
+            'Content-Type': 'application/json',
+            'Node-RED-API-Version': 'v2',
+            Authorization: 'Bearer test-token',
+            Accept: 'text/html',
+          },
+        }
+      );
+    });
+
+    it('should URL-encode module and set for scoped packages', async () => {
+      const mockHtml = '<p>Scoped package help.</p>';
+
+      vi.mocked(request).mockResolvedValue({
+        statusCode: 200,
+        body: { text: vi.fn().mockResolvedValue(mockHtml) },
+      } as any);
+
+      await client.getNodeHelp('@scope/node-red-contrib-foo', 'foo-node');
+      expect(request).toHaveBeenCalledWith(
+        'http://localhost:1880/nodes/%40scope%2Fnode-red-contrib-foo/foo-node',
+        expect.objectContaining({ method: 'GET' })
+      );
+    });
+
+    it('should throw error on 404', async () => {
+      vi.mocked(request).mockResolvedValue({
+        statusCode: 404,
+        body: { text: vi.fn().mockResolvedValue('Not Found') },
+      } as any);
+      await expect(
+        client.getNodeHelp('nonexistent-module', 'nonexistent-set')
+      ).rejects.toThrow('Failed to get node help: 404');
+    });
+
+    it('should throw error on 401', async () => {
+      vi.mocked(request).mockResolvedValue({
+        statusCode: 401,
+        body: { text: vi.fn().mockResolvedValue('Unauthorized') },
+      } as any);
+      await expect(
+        client.getNodeHelp('node-red', 'inject')
+      ).rejects.toThrow('Failed to get node help: 401');
+    });
+  });
 });

tests/server.test.ts

@@ -42,7 +42,7 @@ describe('MCP Server', () => {
     expect(() => createServer()).toThrow();
   });
 
-  it('should list delete_flow in available tools', async () => {
+  it('should list all tools including get_node_help', async () => {
     process.env.NODE_RED_URL = 'http://localhost:1880';
     process.env.NODE_RED_TOKEN = 'test-token';
 
@@ -61,6 +61,7 @@ describe('MCP Server', () => {
     expect(toolNames).toContain('update_flow');
     expect(toolNames).toContain('validate_flow');
     expect(toolNames).toContain('delete_flow');
+    expect(toolNames).toContain('get_node_help');
 
     await client.close();
     await server.close();

tests/tools-runtime.test.ts

@@ -1,6 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest';
 import type { NodeRedClient } from '../src/client.js';
 import { getDiagnostics } from '../src/tools/get-diagnostics.js';
+import { getNodeHelp } from '../src/tools/get-node-help.js';
 import { getSettings } from '../src/tools/get-settings.js';
 
 describe('Runtime Info Tool Handlers', () => {
@@ -10,6 +11,7 @@ describe('Runtime Info Tool Handlers', () => {
     mockClient = {
       getSettings: vi.fn(),
       getDiagnostics: vi.fn(),
+      getNodeHelp: vi.fn(),
     } as any;
   });
 
@@ -57,4 +59,35 @@ describe('Runtime Info Tool Handlers', () => {
       expect(JSON.parse(result.content[0].text)).toEqual({});
     });
   });
+
+  describe('getNodeHelp', () => {
+    it('should return HTML help content', async () => {
+      const mockHtml = '<p>This node connects to a Zigbee2MQTT device.</p>';
+      vi.mocked(mockClient.getNodeHelp).mockResolvedValue(mockHtml);
+      const result = await getNodeHelp(mockClient, {
+        module: 'node-red-contrib-zigbee2mqtt',
+        set: 'zigbee2mqtt-in',
+      });
+      expect(result.content).toHaveLength(1);
+      expect(result.content[0].type).toBe('text');
+      expect(result.content[0].text).toBe(mockHtml);
+    });
+
+    it('should return help for core nodes', async () => {
+      const mockHtml = '<p>Injects a message into a flow.</p>';
+      vi.mocked(mockClient.getNodeHelp).mockResolvedValue(mockHtml);
+      const result = await getNodeHelp(mockClient, {
+        module: 'node-red',
+        set: 'inject',
+      });
+      expect(result.content).toHaveLength(1);
+      expect(result.content[0].text).toBe(mockHtml);
+    });
+
+    it('should reject invalid arguments', async () => {
+      await expect(getNodeHelp(mockClient, {})).rejects.toThrow();
+      await expect(getNodeHelp(mockClient, { module: 'foo' })).rejects.toThrow();
+      await expect(getNodeHelp(mockClient, { set: 'bar' })).rejects.toThrow();
+    });
+  });
 });