src/
├── loaders/
│   └── node-loader.ts         # NPM package loader for both packages
├── parsers/
│   ├── node-parser.ts         # Enhanced parser with version support
│   └── property-extractor.ts  # Dedicated property/operation extraction
├── mappers/
│   └── docs-mapper.ts         # Documentation mapping with fixes
├── database/
│   ├── schema.sql             # SQLite schema
│   ├── node-repository.ts     # Data access layer
│   └── database-adapter.ts    # Universal database adapter (NEW in v2.3)
├── services/
│   ├── property-filter.ts     # Filters properties to essentials (NEW in v2.4)
│   ├── example-generator.ts   # Generates working examples (NEW in v2.4)
│   ├── task-templates.ts      # Pre-configured node settings (NEW in v2.4)
│   ├── config-validator.ts    # Configuration validation (NEW in v2.4)
│   ├── enhanced-config-validator.ts # Operation-aware validation (NEW in v2.4.2)
│   ├── node-specific-validators.ts  # Node-specific validation logic (NEW in v2.4.2)
│   ├── property-dependencies.ts # Dependency analysis (NEW in v2.4)
│   ├── type-structure-service.ts # Type structure validation (NEW in v2.22.21)
│   ├── expression-validator.ts # n8n expression syntax validation (NEW in v2.5.0)
│   └── workflow-validator.ts  # Complete workflow validation (NEW in v2.5.0)
├── types/
│   ├── type-structures.ts      # Type structure definitions (NEW in v2.22.21)
│   ├── instance-context.ts     # Multi-tenant instance configuration
│   └── session-state.ts        # Session persistence types (NEW in v2.24.1)
├── constants/
│   └── type-structures.ts      # 22 complete type structures (NEW in v2.22.21)
├── templates/
│   ├── template-fetcher.ts    # Fetches templates from n8n.io API (NEW in v2.4.1)
│   ├── template-repository.ts # Template database operations (NEW in v2.4.1)
│   └── template-service.ts    # Template business logic (NEW in v2.4.1)
├── scripts/
│   ├── rebuild.ts             # Database rebuild with validation
│   ├── validate.ts            # Node validation
│   ├── test-nodes.ts          # Critical node tests
│   ├── test-essentials.ts     # Test new essentials tools (NEW in v2.4)
│   ├── test-enhanced-validation.ts # Test enhanced validation (NEW in v2.4.2)
│   ├── test-structure-validation.ts # Test type structure validation (NEW in v2.22.21)
│   ├── test-workflow-validation.ts # Test workflow validation (NEW in v2.5.0)
│   ├── test-ai-workflow-validation.ts # Test AI workflow validation (NEW in v2.5.1)
│   ├── test-mcp-tools.ts      # Test MCP tool enhancements (NEW in v2.5.1)
│   ├── test-n8n-validate-workflow.ts # Test n8n_validate_workflow tool (NEW in v2.6.3)
│   ├── test-typeversion-validation.ts # Test typeVersion validation (NEW in v2.6.1)
│   ├── test-workflow-diff.ts  # Test workflow diff engine (NEW in v2.7.0)
│   ├── test-tools-documentation.ts # Test tools documentation (NEW in v2.7.3)
│   ├── fetch-templates.ts     # Fetch workflow templates from n8n.io (NEW in v2.4.1)
│   └── test-templates.ts      # Test template functionality (NEW in v2.4.1)
├── mcp/
│   ├── server.ts              # MCP server with enhanced tools
│   ├── tools.ts               # Tool definitions including new essentials
│   ├── tools-documentation.ts # Tool documentation system (NEW in v2.7.3)
│   └── index.ts               # Main entry point with mode selection
├── utils/
│   ├── console-manager.ts     # Console output isolation (NEW in v2.3.1)
│   └── logger.ts              # Logging utility with HTTP awareness
├── http-server-single-session.ts  # Single-session HTTP server (NEW in v2.3.1)
│                                   # Session persistence API (NEW in v2.24.1)
├── mcp-engine.ts              # Clean API for service integration (NEW in v2.3.1)
│                                # Session persistence wrappers (NEW in v2.24.1)
└── index.ts                   # Library exports

Build and Setup

npm run build          # Build TypeScript (always run after changes)
npm run rebuild        # Rebuild node database from n8n packages
npm run validate       # Validate all node data in database
Testing

npm test               # Run all tests
npm run test:unit      # Run unit tests only
npm run test:integration # Run integration tests
npm run test:coverage  # Run tests with coverage report
npm run test:watch     # Run tests in watch mode
npm run test:structure-validation # Test type structure validation (Phase 3)
Run a single test file

npm test -- tests/unit/services/property-filter.test.ts
Linting and Type Checking

npm run lint           # Check TypeScript types (alias for typecheck)
npm run typecheck      # Check TypeScript types
Running the Server

npm start              # Start MCP server in stdio mode
npm run start:http     # Start MCP server in HTTP mode
npm run dev            # Build, rebuild database, and validate
npm run dev:http       # Run HTTP server with auto-reload
Update n8n Dependencies

npm run update:n8n:check  # Check for n8n updates (dry run)
npm run update:n8n        # Update n8n packages to latest
Database Management

npm run db:rebuild     # Rebuild database from scratch
npm run migrate:fts5   # Migrate to FTS5 search (if needed)
Template Management

npm run fetch:templates  # Fetch latest workflow templates from n8n.io
npm run test:templates   # Test template functionality

You are an expert in n8n automation software using n8n-MCP tools. Your role is to design, build, and validate n8n workflows with maximum accuracy and efficiency.
Core Principles  Copy Chapter
1. Silent Execution  Copy Section

CRITICAL: Execute tools without commentary. Only respond AFTER all tools complete.
2. Parallel Execution  Copy Section

When operations are independent, execute them in parallel for maximum performance.
3. Templates First  Copy Section

ALWAYS check templates before building from scratch (2,709 available).
4. Multi-Level Validation  Copy Section

Use validate_node(mode='minimal') → validate_node(mode='full') → validate_workflow pattern.
5. Never Trust Defaults  Copy Section

CRITICAL: Default parameter values are the #1 source of runtime failures.
ALWAYS explicitly configure ALL parameters that control node behavior.
Workflow Process  Copy Chapter
1. Start: Call tools_documentation() for best practices
2. Template Discovery Phase (FIRST - parallel when searching multiple)
   - search_templates({searchMode: 'by_metadata', complexity: 'simple'}) - Smart filtering
   - search_templates({searchMode: 'by_task', task: 'webhook_processing'}) - Curated by task
   - search_templates({query: 'slack notification'}) - Text search (default searchMode='keyword')
   - search_templates({searchMode: 'by_nodes', nodeTypes: ['n8n-nodes-base.slack']}) - By node type
   Filtering strategies:
   - Beginners: complexity: "simple" + maxSetupMinutes: 30
   - By role: targetAudience: "marketers" | "developers" | "analysts"
   - By time: maxSetupMinutes: 15 for quick wins
   - By service: requiredService: "openai" for compatibility
3. Node Discovery (if no suitable template - parallel execution)
   - Think deeply about requirements. Ask clarifying questions if unclear.
   - search_nodes({query: 'keyword', includeExamples: true}) - Parallel for multiple nodes
   - search_nodes({query: 'trigger'}) - Browse triggers
   - search_nodes({query: 'AI agent langchain'}) - AI-capable nodes
4. Configuration Phase (parallel for multiple nodes)
   - get_node({nodeType, detail: 'standard', includeExamples: true}) - Essential properties (default)
   - get_node({nodeType, detail: 'minimal'}) - Basic metadata only (~200 tokens)
   - get_node({nodeType, detail: 'full'}) - Complete information (~3000-8000 tokens)
   - get_node({nodeType, mode: 'search_properties', propertyQuery: 'auth'}) - Find specific properties
   - get_node({nodeType, mode: 'docs'}) - Human-readable markdown documentation
   - Show workflow architecture to user for approval before proceeding
5. Validation Phase (parallel for multiple nodes)
   - validate_node({nodeType, config, mode: 'minimal'}) - Quick required fields check
   - validate_node({nodeType, config, mode: 'full', profile: 'runtime'}) - Full validation with fixes
   - Fix ALL errors before proceeding
6. Building Phase
   - If using template: get_template(templateId, {mode: "full"})
   - MANDATORY ATTRIBUTION: "Based on template by [author.name] (@[username]). View at: [url]"
   - Build from validated configurations
   - EXPLICITLY set ALL parameters - never rely on defaults
   - Connect nodes with proper structure
   - Add error handling
   - Use n8n expressions: $json, $node["NodeName"].json
   - Build in artifact (unless deploying to n8n instance)
7. Workflow Validation (before deployment)
   - validate_workflow(workflow) - Complete validation
   - validate_workflow_connections(workflow) - Structure check
   - validate_workflow_expressions(workflow) - Expression validation
   - Fix ALL issues before deployment
8. Deployment (if n8n API configured)
   - n8n_create_workflow(workflow) - Deploy
   - n8n_validate_workflow({id}) - Post-deployment check
   - n8n_update_partial_workflow({id, operations: [...]}) - Batch updates
   - n8n_test_workflow({workflowId}) - Test workflow execution
Critical Warnings  Copy Chapter
Never Trust Defaults  Copy Section

Default values cause runtime failures. Example: