Refactor to focused n8n node documentation MCP server

Major refactoring to align with actual requirements:
- Purpose: Serve n8n node code/documentation to AI agents only
- No workflow execution or management features
- Complete node information including source code, docs, and examples

New features:
- Node documentation service with SQLite FTS5 search
- Documentation fetcher from n8n-docs repository
- Example workflow generator for each node type
- Simplified MCP tools focused on node information
- Complete database rebuild with all node data

MCP Tools:
- list_nodes: List available nodes
- get_node_info: Get complete node information
- search_nodes: Full-text search across nodes
- get_node_example: Get usage examples
- get_node_source_code: Get source code only
- get_node_documentation: Get documentation only
- rebuild_database: Rebuild entire database
- get_database_statistics: Database stats

Database schema includes:
- Node source code and metadata
- Official documentation from n8n-docs
- Generated usage examples
- Full-text search capabilities
- Category and type filtering

Updated README with:
- Clear purpose statement
- Claude Desktop installation instructions
- Complete tool documentation
- Troubleshooting guide

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/test-node-documentation-service.js

@@ -0,0 +1,88 @@
+#!/usr/bin/env node
+
+const { NodeDocumentationService } = require('../dist/services/node-documentation-service');
+
+async function testService() {
+  console.log('=== Testing Node Documentation Service ===\n');
+  
+  // Use a separate database for v2
+  const service = new NodeDocumentationService('./data/nodes-v2.db');
+  
+  try {
+    // Test 1: List nodes
+    console.log('1️⃣ Testing list nodes...');
+    const nodes = await service.listNodes();
+    console.log(`   Found ${nodes.length} nodes in database`);
+    
+    if (nodes.length === 0) {
+      console.log('\n⚠️  No nodes found. Running rebuild...');
+      const stats = await service.rebuildDatabase();
+      console.log(`   Rebuild complete: ${stats.successful} nodes stored`);
+    }
+    
+    // Test 2: Get specific node info (IF node)
+    console.log('\n2️⃣ Testing get node info for "If" node...');
+    const ifNode = await service.getNodeInfo('n8n-nodes-base.if');
+    
+    if (ifNode) {
+      console.log('   ✅ Found IF node:');
+      console.log(`      Name: ${ifNode.displayName}`);
+      console.log(`      Description: ${ifNode.description}`);
+      console.log(`      Has source code: ${!!ifNode.sourceCode}`);
+      console.log(`      Source code length: ${ifNode.sourceCode?.length || 0} bytes`);
+      console.log(`      Has documentation: ${!!ifNode.documentation}`);
+      console.log(`      Has example: ${!!ifNode.exampleWorkflow}`);
+      
+      if (ifNode.exampleWorkflow) {
+        console.log('\n   📋 Example workflow:');
+        console.log(JSON.stringify(ifNode.exampleWorkflow, null, 2).substring(0, 500) + '...');
+      }
+    } else {
+      console.log('   ❌ IF node not found');
+    }
+    
+    // Test 3: Search nodes
+    console.log('\n3️⃣ Testing search functionality...');
+    
+    // Search for webhook nodes
+    const webhookNodes = await service.searchNodes({ query: 'webhook' });
+    console.log(`\n   🔍 Search for "webhook": ${webhookNodes.length} results`);
+    webhookNodes.slice(0, 3).forEach(node => {
+      console.log(`      - ${node.displayName} (${node.nodeType})`);
+    });
+    
+    // Search for HTTP nodes
+    const httpNodes = await service.searchNodes({ query: 'http' });
+    console.log(`\n   🔍 Search for "http": ${httpNodes.length} results`);
+    httpNodes.slice(0, 3).forEach(node => {
+      console.log(`      - ${node.displayName} (${node.nodeType})`);
+    });
+    
+    // Test 4: Get statistics
+    console.log('\n4️⃣ Testing database statistics...');
+    const stats = service.getStatistics();
+    console.log('   📊 Database stats:');
+    console.log(`      Total nodes: ${stats.totalNodes}`);
+    console.log(`      Nodes with docs: ${stats.nodesWithDocs}`);
+    console.log(`      Nodes with examples: ${stats.nodesWithExamples}`);
+    console.log(`      Trigger nodes: ${stats.triggerNodes}`);
+    console.log(`      Webhook nodes: ${stats.webhookNodes}`);
+    console.log(`      Total packages: ${stats.totalPackages}`);
+    
+    // Test 5: Category filtering
+    console.log('\n5️⃣ Testing category filtering...');
+    const coreNodes = await service.searchNodes({ category: 'Core Nodes' });
+    console.log(`   Found ${coreNodes.length} core nodes`);
+    
+    console.log('\n✅ All tests completed!');
+    
+  } catch (error) {
+    console.error('\n❌ Test failed:', error);
+    process.exit(1);
+  } finally {
+    service.close();
+  }
+}
+
+// Run tests
+testService().catch(console.error);

tests/test-node-list.js

@@ -0,0 +1,26 @@
+#!/usr/bin/env node
+
+const { NodeSourceExtractor } = require('../dist/utils/node-source-extractor');
+
+async function testNodeList() {
+  console.log('Testing node list...\n');
+  
+  const extractor = new NodeSourceExtractor();
+  
+  try {
+    const nodes = await extractor.listAvailableNodes();
+    
+    console.log(`Total nodes found: ${nodes.length}`);
+    
+    // Show first 5 nodes
+    console.log('\nFirst 5 nodes:');
+    nodes.slice(0, 5).forEach((node, index) => {
+      console.log(`${index + 1}. Node:`, JSON.stringify(node, null, 2));
+    });
+    
+  } catch (error) {
+    console.error('Error:', error);
+  }
+}
+
+testNodeList();

tests/test-small-rebuild.js

@@ -0,0 +1,62 @@
+#!/usr/bin/env node
+
+const { NodeDocumentationService } = require('../dist/services/node-documentation-service');
+
+async function testSmallRebuild() {
+  console.log('Testing small rebuild...\n');
+  
+  const service = new NodeDocumentationService('./data/nodes-v2-test.db');
+  
+  try {
+    // First, let's just try the IF node specifically
+    const extractor = service.extractor;
+    console.log('1️⃣ Testing extraction of IF node...');
+    
+    try {
+      const ifNodeData = await extractor.extractNodeSource('n8n-nodes-base.If');
+      console.log('   ✅ Successfully extracted IF node');
+      console.log('   Source code length:', ifNodeData.sourceCode.length);
+      console.log('   Has credentials:', !!ifNodeData.credentialCode);
+    } catch (error) {
+      console.log('   ❌ Failed to extract IF node:', error.message);
+    }
+    
+    // Try the Webhook node
+    console.log('\n2️⃣ Testing extraction of Webhook node...');
+    try {
+      const webhookNodeData = await extractor.extractNodeSource('n8n-nodes-base.Webhook');
+      console.log('   ✅ Successfully extracted Webhook node');
+      console.log('   Source code length:', webhookNodeData.sourceCode.length);
+    } catch (error) {
+      console.log('   ❌ Failed to extract Webhook node:', error.message);
+    }
+    
+    // Now try storing just these nodes
+    console.log('\n3️⃣ Testing storage of a single node...');
+    const nodeInfo = {
+      nodeType: 'n8n-nodes-base.If',
+      name: 'If',
+      displayName: 'If',
+      description: 'Route items based on comparison operations',
+      sourceCode: 'test source code',
+      packageName: 'n8n-nodes-base',
+      hasCredentials: false,
+      isTrigger: false,
+      isWebhook: false
+    };
+    
+    await service.storeNode(nodeInfo);
+    console.log('   ✅ Successfully stored test node');
+    
+    // Check if it was stored
+    const retrievedNode = await service.getNodeInfo('n8n-nodes-base.If');
+    console.log('   Retrieved node:', retrievedNode ? 'Found' : 'Not found');
+    
+  } catch (error) {
+    console.error('❌ Test failed:', error);
+  } finally {
+    service.close();
+  }
+}
+
+testSmallRebuild();