n8n-mcp/CLAUDE.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

n8n-mcp is a comprehensive documentation and knowledge server that provides AI assistants with complete access to n8n node information through the Model Context Protocol (MCP). It serves as a bridge between n8n's workflow automation platform and AI models, enabling them to understand and work with n8n nodes effectively.

✅ Latest Updates (v2.7.0)

Update (v2.7.0) - Diff-Based Workflow Editing with Transactional Updates:

• ✅ NEW: n8n_update_partial_workflow tool - Update workflows using diff operations for precise, incremental changes
• ✅ RENAMED: n8n_update_workflow → n8n_update_full_workflow - Clarifies that it replaces the entire workflow
• ✅ NEW: WorkflowDiffEngine - Applies targeted edits without sending full workflow JSON
• ✅ 80-90% token savings - Only send the changes, not the entire workflow
• ✅ 13 diff operations - addNode, removeNode, updateNode, moveNode, enableNode, disableNode, addConnection, removeConnection, updateConnection, updateSettings, updateName, addTag, removeTag
• ✅ Smart node references - Use either node ID or name for operations
• ✅ Transaction safety - Validates all operations before applying any changes
• ✅ Validation-only mode - Test your diff operations without applying them
• ✅ Comprehensive test coverage - All operations and edge cases tested
• ✅ Example guide - See workflow-diff-examples.md for usage patterns
• ✅ FIXED: MCP validation error - Simplified schema to fix "additional properties" error in Claude Desktop
• ✅ FIXED: n8n API validation - Updated cleanWorkflowForUpdate to remove all read-only fields
• ✅ FIXED: Claude Desktop compatibility - Added additionalProperties: true to handle extra metadata from Claude Desktop
• ✅ NEW: Transactional Updates - Two-pass processing allows adding nodes and connections in any order
• ✅ Operation Limit - Maximum 5 operations per request ensures reliability
• ✅ Order Independence - Add connections before nodes - engine handles dependencies automatically

Update (v2.6.3) - n8n Instance Workflow Validation:

• ✅ NEW: n8n_validate_workflow tool - Validate workflows directly from n8n instance by ID
• ✅ Fetches and validates - Retrieves workflow from n8n API and runs comprehensive validation
• ✅ Same validation logic - Uses existing WorkflowValidator for consistency
• ✅ Full validation options - Supports all validation profiles and options
• ✅ Integrated workflow - Part of complete lifecycle: discover → build → validate → deploy → execute
• ✅ No JSON needed - AI agents can validate by just providing workflow ID

Update (v2.6.2) - Enhanced Workflow Creation Validation:

• ✅ NEW: Node type validation - Verifies node types actually exist in n8n
• ✅ FIXED: nodes-base prefix detection - Now catches nodes-base.webhook BEFORE database lookup
• ✅ NEW: Smart suggestions - Detects nodes-base.webhook and suggests n8n-nodes-base.webhook
• ✅ NEW: Common mistake detection - Catches missing package prefixes (e.g., webhook → n8n-nodes-base.webhook)
• ✅ NEW: Minimum viable workflow validation - Prevents single-node workflows (except webhooks)
• ✅ NEW: Empty connection detection - Catches multi-node workflows with no connections
• ✅ Enhanced error messages - Clear guidance on proper workflow structure
• ✅ Connection examples - Shows correct format: connections: { "Node Name": { "main": [[{ "node": "Target", "type": "main", "index": 0 }]] } }
• ✅ Helper functions - getWorkflowStructureExample() and getWorkflowFixSuggestions()
• ✅ Prevents broken workflows - Like single webhook nodes with empty connections that show as question marks
• ✅ Reinforces best practices - Use node NAMES (not IDs) in connections

Update (v2.6.1) - Enhanced typeVersion Validation:

• ✅ NEW: typeVersion validation - Workflow validator now enforces typeVersion on all versioned nodes
• ✅ Catches missing typeVersion - Returns error with correct version to use
• ✅ Warns on outdated versions - Alerts when using older node versions
• ✅ Prevents invalid versions - Errors on versions that exceed maximum supported
• ✅ Helps AI agents avoid common workflow creation mistakes
• ✅ Ensures workflows use compatible node versions before deployment

Update (v2.6.0) - n8n Management Tools Integration:

• ✅ NEW: 14 n8n management tools - Create, update, execute workflows via API
• ✅ NEW: n8n_create_workflow - Create workflows programmatically
• ✅ NEW: n8n_update_workflow - Update existing workflows
• ✅ NEW: n8n_trigger_webhook_workflow - Execute workflows via webhooks
• ✅ NEW: n8n_list_executions - Monitor workflow executions
• ✅ NEW: n8n_health_check - Check n8n instance connectivity
• ✅ Integrated n8n-manager-for-ai-agents functionality
• ✅ Optional feature - only enabled when N8N_API_URL and N8N_API_KEY configured
• ✅ Complete workflow lifecycle: discover → build → validate → deploy → execute
• ✅ Smart error handling for API limitations (activation, direct execution)
• ✅ Conditional tool registration based on configuration

✅ Previous Updates (v2.5.1)

Update (v2.5.1) - AI Tool Support Enhancements:

• ✅ NEW: get_node_as_tool_info tool - Get specific information about using ANY node as an AI tool
• ✅ Enhanced: get_node_info - Now includes aiToolCapabilities section for all nodes
• ✅ Enhanced: list_ai_tools - Added usage guidance explaining ANY node can be used as a tool
• ✅ Enhanced: WorkflowValidator - Now validates ai_tool connections in workflows
• ✅ AI workflow pattern detection - Warns when AI Agents have no tools connected
• ✅ Community node detection - Reminds about N8N_COMMUNITY_PACKAGES_ALLOW_TOOL_USAGE environment variable
• ✅ NEW: AI Tool TaskTemplates - Added use_google_sheets_as_tool, use_slack_as_tool, multi_tool_ai_agent
• ✅ Comprehensive examples showing how to connect regular nodes as AI tools
• ✅ Tool usage documentation with $fromAI() expression examples

Update (v2.5.0) - Complete Workflow Validation:

• ✅ NEW: validate_workflow tool - Validate entire workflows before deployment
• ✅ NEW: validate_workflow_connections tool - Check workflow structure and connections
• ✅ NEW: validate_workflow_expressions tool - Validate all n8n expressions in a workflow
• ✅ NEW: ExpressionValidator - Comprehensive n8n expression syntax validation
• ✅ NEW: WorkflowValidator - Complete workflow structure and logic validation
• ✅ Detects cycles (infinite loops) in workflows
• ✅ Validates node references in expressions ($node["Node Name"])
• ✅ Checks for orphaned nodes and missing connections
• ✅ Expression syntax validation with common mistake detection
• ✅ Workflow best practices analysis with suggestions
• ✅ Supports partial validation (nodes only, connections only, expressions only)
• ✅ Test coverage for all validation scenarios

Update (v2.4.2) - Enhanced Node Configuration Validation:

• ✅ NEW: validate_node_operation tool - Operation-aware validation with 80%+ fewer false positives
• ✅ NEW: validate_node_minimal tool - Lightning-fast validation for just required fields
• ✅ NEW: Validation profiles - Choose between minimal, runtime, ai-friendly, or strict validation
• ✅ NEW: EnhancedConfigValidator - Smart validation that only checks relevant properties
• ✅ NEW: Node-specific validators - Custom logic for Slack, Google Sheets, OpenAI, MongoDB, Webhook, Postgres, MySQL
• ✅ NEW: SQL safety features - Detects SQL injection risks, unsafe DELETE/UPDATE queries
• ✅ Added operation context filtering (only validates properties for selected operation)
• ✅ Integrated working examples in validation responses when errors found
• ✅ Added actionable next steps and auto-fix suggestions
• ✅ Basic code syntax validation for JavaScript/Python in Code node
• ✅ Dramatic improvement for complex multi-operation nodes
• ✅ Test results: Slack validation reduced from 45 errors to 1 error!

Update (v2.4.1) - n8n Workflow Templates:

• ✅ NEW: list_node_templates tool - Find workflow templates using specific nodes
• ✅ NEW: get_template tool - Get complete workflow JSON for import
• ✅ NEW: search_templates tool - Search templates by keywords
• ✅ NEW: get_templates_for_task tool - Get curated templates for common tasks
• ✅ Added Templates system with n8n.io API integration
• ✅ Templates filtered to last 6 months only (freshness guarantee)
• ✅ Manual fetch system - not part of regular rebuild
• ✅ Full workflow JSON available for immediate use
• ✅ 10 task categories: AI automation, data sync, webhooks, etc.

Update (v2.4.0) - AI-Optimized MCP Tools:

• ✅ NEW: get_node_essentials tool - Returns only 10-20 essential properties (95% size reduction)
• ✅ NEW: search_node_properties tool - Search for specific properties within nodes
• ✅ NEW: get_node_for_task tool - Pre-configured settings for 14 common tasks
• ✅ NEW: list_tasks tool - Discover available task templates
• ✅ NEW: validate_node_config tool - Validate configurations before use
• ✅ NEW: get_property_dependencies tool - Analyze property visibility dependencies
• ✅ Added PropertyFilter service with curated essential properties for 20+ nodes
• ✅ Added ExampleGenerator with working examples for common use cases
• ✅ Added TaskTemplates service with 14 pre-configured tasks
• ✅ Added ConfigValidator service for comprehensive validation
• ✅ Added PropertyDependencies service for dependency analysis
• ✅ Enhanced all property descriptions - 100% coverage
• ✅ Added version information to essentials response
• ✅ Dramatically improved AI agent experience for workflow building
• ✅ Response sizes reduced from 100KB+ to <5KB for common nodes

Update (v2.3.3) - Automated Dependency Updates & Validation Fixes:

• ✅ Implemented automated n8n dependency update system
• ✅ Created GitHub Actions workflow for weekly updates
• ✅ Fixed validation script to use correct node type format
• ✅ Successfully updated to n8n v1.97.1 with all dependencies in sync
• ✅ All 525 nodes loading correctly with validation passing

Previous Update (v2.3.2) - Complete MCP HTTP Fix:

• ✅ Fixed "stream is not readable" error by removing body parsing middleware
• ✅ Fixed "Server not initialized" error with direct JSON-RPC implementation
• ✅ Created http-server-fixed.ts that bypasses StreamableHTTPServerTransport issues
• ✅ Full MCP protocol compatibility without transport complications
• ✅ Use USE_FIXED_HTTP=true environment variable to enable the fixed server

Previous Update (v2.3) - Universal Node.js Compatibility:

• ✅ Automatic database adapter fallback system implemented
• ✅ Works with ANY Node.js version (no more v20.17.0 requirement)
• ✅ Seamless fallback from better-sqlite3 to sql.js
• ✅ No manual configuration needed for Claude Desktop
• ✅ Maintains full functionality with either adapter

✅ Previous Achievements (v2.2)

The major refactor has been successfully completed based on IMPLEMENTATION_PLAN.md v2.2

Achieved Goals:

• ✅ Fixed property/operation extraction (452/458 nodes have properties)
• ✅ Added AI tool detection (35 AI tools detected)
• ✅ Full support for @n8n/n8n-nodes-langchain package
• ✅ Proper VersionedNodeType handling
• ✅ Fixed documentation mapping issues

Current Architecture:

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)
│   ├── expression-validator.ts # n8n expression syntax validation (NEW in v2.5.0)
│   └── workflow-validator.ts  # Complete workflow validation (NEW in v2.5.0)
├── 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-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)
│   ├── 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-update.ts       # MCP server with enhanced tools
│   ├── tools-update.ts        # Tool definitions including new essentials
│   └── 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)
├── mcp-engine.ts              # Clean API for service integration (NEW in v2.3.1)
└── index.ts                   # Library exports

Key Metrics:

• 525 nodes successfully loaded (100%) - Updated to n8n v1.97.1
• 520 nodes with properties (99%)
• 334 nodes with operations (63.6%)
• 457 nodes with documentation (87%)
• 263 AI-capable tools detected (major increase)
• All critical nodes pass validation

Key Commands

# Development
npm install          # Install dependencies
npm run build        # Build TypeScript (required before running)
npm run dev          # Run in development mode with auto-reload
npm test             # Run Jest tests
npm run typecheck    # TypeScript type checking
npm run lint         # Check TypeScript types (alias for typecheck)

# Core Commands:
npm run rebuild      # Rebuild node database
npm run rebuild:optimized  # Build database with embedded source code
npm run validate     # Validate critical nodes
npm run test-nodes   # Test critical node properties/operations

# Template Commands:
npm run fetch:templates   # Fetch workflow templates from n8n.io (manual)
npm run fetch:templates:robust  # Robust template fetching with retries
npm run test:templates    # Test template functionality

# Test Commands:
npm run test:essentials     # Test new essentials tools
npm run test:enhanced-validation  # Test enhanced validation
npm run test:ai-workflow-validation  # Test AI workflow validation
npm run test:mcp-tools      # Test MCP tool enhancements
npm run test:single-session # Test single session HTTP
npm run test:template-validation  # Test template validation
npm run test:n8n-manager   # Test n8n management tools integration
npm run test:n8n-validate-workflow  # Test n8n_validate_workflow tool
npm run test:typeversion-validation  # Test typeVersion validation
npm run test:workflow-diff  # Test workflow diff engine

# Workflow Validation Commands:
npm run test:workflow-validation   # Test workflow validation features

# Dependency Update Commands:
npm run update:n8n:check  # Check for n8n updates (dry run)
npm run update:n8n        # Update n8n packages to latest versions

# HTTP Server Commands:
npm run start:http   # Start server in HTTP mode
npm run start:http:fixed    # Start with fixed HTTP implementation
npm run start:http:legacy   # Start with legacy HTTP server
npm run http         # Build and start HTTP server
npm run dev:http     # HTTP server with auto-reload

# Legacy Commands (deprecated):
npm run db:rebuild   # Old rebuild command
npm run db:init      # Initialize empty database
npm run docs:rebuild # Rebuild documentation from TypeScript source

# Production
npm start            # Run built application (stdio mode)
npm run start:http   # Run in HTTP mode for remote access

# Docker Commands:
docker compose up -d        # Start with Docker Compose
docker compose logs -f      # View logs
docker compose down         # Stop containers
docker compose down -v      # Stop and remove volumes
./scripts/test-docker.sh    # Test Docker deployment

Docker Deployment

The project includes ultra-optimized Docker support with NO n8n dependencies at runtime:

🚀 Key Optimization: Runtime-Only Dependencies

Important: Since the database is always pre-built before deployment, the Docker image contains NO n8n dependencies. This results in:

• 82% smaller images (~280MB vs ~1.5GB)
• 10x faster builds (~1-2 minutes vs ~12 minutes)
• No n8n version conflicts at runtime
• Minimal attack surface for security

Quick Start with Docker

# IMPORTANT: Rebuild database first (requires n8n locally)
npm run rebuild

# Create .env file with auth token
echo "AUTH_TOKEN=$(openssl rand -base64 32)" > .env

# Start the server
docker compose up -d

# Check health
curl http://localhost:3000/health

Docker Architecture

The Docker image contains ONLY these runtime dependencies:

• @modelcontextprotocol/sdk - MCP protocol implementation
• better-sqlite3 / sql.js - SQLite database access
• express - HTTP server mode
• dotenv - Environment configuration

Docker Features

• Ultra-optimized size (~280MB runtime-only)
• No n8n dependencies in production image
• Pre-built database required (nodes.db)
• BuildKit optimizations for fast builds
• Non-root user execution for security
• Health checks built into the image

Docker Images

• ghcr.io/czlonkowski/n8n-mcp:latest - Runtime-only production image
• Multi-architecture support (amd64, arm64)
• ~280MB compressed size (82% smaller!)

Docker Development

# Use BuildKit compose for development
COMPOSE_DOCKER_CLI_BUILD=1 docker-compose -f docker-compose.buildkit.yml up

# Build with optimizations
./scripts/build-optimized.sh

# Run tests
./scripts/test-docker.sh

For detailed Docker documentation, see DOCKER_README.md.

High-Level Architecture

The project implements MCP (Model Context Protocol) to expose n8n node documentation, source code, and examples to AI assistants. Key architectural components:

Core Services

• NodeDocumentationService (src/services/node-documentation-service.ts): Main database service using SQLite with FTS5 for fast searching
• MCP Server (src/mcp/server.ts): Implements MCP protocol with tools for querying n8n nodes
• Node Source Extractor (src/utils/node-source-extractor.ts): Extracts node implementations from n8n packages
• Enhanced Documentation Fetcher (src/utils/enhanced-documentation-fetcher.ts): Fetches and parses official n8n documentation

MCP Tools Available

• list_nodes - List all available n8n nodes with filtering
• get_node_info - Get comprehensive information about a specific node (now includes aiToolCapabilities)
• get_node_essentials - NEW Get only essential properties (10-20) with examples (95% smaller)
• get_node_as_tool_info - NEW v2.5.1 Get specific information about using ANY node as an AI tool
• search_nodes - Full-text search across all node documentation
• search_node_properties - NEW Search for specific properties within a node
• get_node_for_task - NEW Get pre-configured node settings for common tasks
• list_tasks - NEW List all available task templates
• validate_node_operation - NEW v2.4.2 Verify node configuration with operation awareness and profiles
• validate_node_minimal - NEW v2.4.2 Quick validation for just required fields
• validate_workflow - NEW v2.5.0 Validate entire workflows before deployment (now validates ai_tool connections)
• validate_workflow_connections - NEW v2.5.0 Check workflow structure and connections
• validate_workflow_expressions - NEW v2.5.0 Validate all n8n expressions in a workflow
• get_property_dependencies - NEW Analyze property dependencies and visibility conditions
• list_ai_tools - List all AI-capable nodes (now includes usage guidance)
• get_node_documentation - Get parsed documentation from n8n-docs
• get_database_statistics - Get database usage statistics and metrics
• list_node_templates - NEW Find workflow templates using specific nodes
• get_template - NEW Get complete workflow JSON for import
• search_templates - NEW Search templates by keywords
• get_templates_for_task - NEW Get curated templates for common tasks

n8n Management Tools (NEW v2.6.0 - Requires API Configuration)

These tools are only available when N8N_API_URL and N8N_API_KEY are configured:

Workflow Management

• n8n_create_workflow - Create new workflows with nodes and connections
• n8n_get_workflow - Get complete workflow by ID
• n8n_get_workflow_details - Get workflow with execution statistics
• n8n_get_workflow_structure - Get simplified workflow structure
• n8n_get_workflow_minimal - Get minimal workflow info
• n8n_update_full_workflow - Update existing workflows (complete replacement)
• n8n_update_partial_workflow - NEW v2.7.0 Update workflows using diff operations
• n8n_delete_workflow - Delete workflows permanently
• n8n_list_workflows - List workflows with filtering
• n8n_validate_workflow - NEW v2.6.3 Validate workflow from n8n instance by ID

Execution Management

• n8n_trigger_webhook_workflow - Trigger workflows via webhook URL
• n8n_get_execution - Get execution details by ID
• n8n_list_executions - List executions with status filtering
• n8n_delete_execution - Delete execution records

System Tools

• n8n_health_check - Check n8n API connectivity and features
• n8n_list_available_tools - List all available management tools

Database Structure

Uses SQLite with enhanced schema:

• nodes table: Core node information with FTS5 indexing
• node_documentation: Parsed markdown documentation
• node_examples: Generated workflow examples
• node_source_code: Complete TypeScript/JavaScript implementations

Important Development Notes

Initial Setup Requirements

1. Clone n8n-docs: git clone https://github.com/n8n-io/n8n-docs.git ../n8n-docs
2. Install Dependencies: npm install
3. Build: npm run build
4. Rebuild Database: npm run rebuild
5. Validate: npm run test-nodes

Key Technical Decisions (v2.3)

1. Database Adapter Implementation:

   • Created DatabaseAdapter interface to abstract database operations
   • Implemented BetterSQLiteAdapter and SQLJSAdapter classes
   • Used factory pattern in createDatabaseAdapter() for automatic selection
   • Added persistence layer for sql.js with debounced saves (100ms)

2. Compatibility Strategy:

   • Primary: Try better-sqlite3 first for performance
   • Fallback: Catch native module errors and switch to sql.js
   • Detection: Check for NODE_MODULE_VERSION errors specifically
   • Logging: Clear messages about which adapter is active

3. Performance Considerations:

   • better-sqlite3: ~10-50x faster for most operations
   • sql.js: ~2-5x slower but acceptable for this use case
   • Auto-save: 100ms debounce prevents excessive disk writes with sql.js
   • Memory: sql.js uses more memory but manageable for our dataset size

Node.js Version Compatibility

The project now features automatic database adapter fallback for universal Node.js compatibility:

1. Primary adapter: Uses better-sqlite3 for optimal performance when available
2. Fallback adapter: Automatically switches to sql.js (pure JavaScript) if:
   • Native modules fail to load
   • Node.js version mismatch detected
   • Running in Claude Desktop or other restricted environments

This means the project works with ANY Node.js version without manual intervention. The adapter selection is automatic and transparent.

Implementation Status

• ✅ Property/operation extraction for 98.7% of nodes
• ✅ Support for both n8n-nodes-base and @n8n/n8n-nodes-langchain
• ✅ AI tool detection (35 tools with usableAsTool property)
• ✅ Versioned node support (HTTPRequest, Code, etc.)
• ✅ Documentation coverage for 88.6% of nodes
• ⏳ Version history tracking (deferred - only current version)
• ⏳ Workflow examples (deferred - using documentation)

Testing Workflow

npm run build        # Always build first
npm test             # Run all tests
npm run typecheck    # Verify TypeScript types

Docker Development

# Local development with stdio
docker-compose -f docker-compose.local.yml up

# HTTP server mode
docker-compose -f docker-compose.http.yml up

Authentication (HTTP mode)

When running in HTTP mode, use Bearer token authentication:

Authorization: Bearer your-auth-token

Architecture Patterns

Service Layer Pattern

All major functionality is implemented as services in src/services/. When adding new features:

1. Create a service class with clear responsibilities
2. Use dependency injection where appropriate
3. Implement proper error handling with custom error types
4. Add comprehensive logging using the logger utility

MCP Tool Implementation

When adding new MCP tools:

1. Define the tool in src/mcp/tools.ts
2. Implement handler in src/mcp/server.ts
3. Add proper input validation
4. Return structured responses matching MCP expectations

Database Access Pattern

• Use prepared statements for all queries
• Implement proper transaction handling
• Use FTS5 for text searching
• Cache frequently accessed data in memory

Database Adapter Pattern (NEW in v2.3)

The project uses a database adapter pattern for universal compatibility:

• Primary adapter: better-sqlite3 - Native SQLite bindings for optimal performance
• Fallback adapter: sql.js - Pure JavaScript implementation for compatibility
• Automatic selection: The system detects and handles version mismatches automatically
• Unified interface: Both adapters implement the same DatabaseAdapter interface
• Transparent operation: Application code doesn't need to know which adapter is active

Environment Configuration

Required environment variables (see .env.example):

# Server Configuration
NODE_ENV=development
PORT=3000
AUTH_TOKEN=your-secure-token

# MCP Configuration  
MCP_SERVER_NAME=n8n-documentation-mcp
MCP_SERVER_VERSION=1.0.0

# Logging
LOG_LEVEL=info

License

This project is licensed under the MIT License. Created by Romuald Czlonkowski @ www.aiadvisors.pl/en.

• ✅ Free for any use (personal, commercial, etc.)
• ✅ Modifications and distribution allowed
• ✅ Can be included in commercial products
• ✅ Can be hosted as a service

Attribution is appreciated but not required. See LICENSE and ATTRIBUTION.md for details.

HTTP Remote Deployment (v2.3.0)

✅ HTTP Server Implementation Complete

The project now includes a simplified HTTP server mode for remote deployments:

• Single-user design: Stateless architecture for private deployments
• Simple token auth: Bearer token authentication
• MCP-compatible: Works with mcp-remote adapter for Claude Desktop
• Easy deployment: Minimal configuration required

Quick Start

# Server setup
export MCP_MODE=http
export AUTH_TOKEN=$(openssl rand -base64 32)
npm run start:http

# Client setup (Claude Desktop config)
{
  "mcpServers": {
    "n8n-remote": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/mcp-remote@latest",
        "connect",
        "https://your-server.com/mcp"
      ],
      "env": {
        "MCP_AUTH_TOKEN": "your-auth-token"
      }
    }
  }
}

Available Scripts

• npm run start:http - Start in HTTP mode
• npm run http - Build and start HTTP server
• npm run dev:http - Development mode with auto-reload
• ./scripts/deploy-http.sh - Deployment helper script

For detailed deployment instructions, see HTTP Deployment Guide.

Recent Problem Solutions

MCP HTTP Server Errors (Solved in v2.3.2)

Problem: Two critical errors prevented the HTTP server from working:

1. "stream is not readable" - Express.json() middleware consumed the request stream
2. "Server not initialized" - StreamableHTTPServerTransport initialization issues

Solution: Two-phase fix:

1. Removed body parsing middleware to preserve raw stream
2. Created direct JSON-RPC implementation bypassing StreamableHTTPServerTransport

Technical Details:

• src/http-server-single-session.ts - Single-session implementation (partial fix)
• src/http-server-fixed.ts - Direct JSON-RPC implementation (complete fix)
• src/utils/console-manager.ts - Console output isolation
• Use USE_FIXED_HTTP=true to enable the fixed implementation

SQLite Version Mismatch (Solved in v2.3)

Problem: Claude Desktop bundles Node.js v16.19.1, causing NODE_MODULE_VERSION errors with better-sqlite3 compiled for different versions.

Solution: Implemented dual-adapter system:

1. Database adapter abstraction layer
2. Automatic fallback from better-sqlite3 to sql.js
3. Transparent operation regardless of Node.js version
4. No manual configuration required

Technical Details:

• src/database/database-adapter.ts - Adapter interface and implementations
• createDatabaseAdapter() - Factory function with automatic selection
• Modified all database operations to use adapter interface
• Added sql.js with persistence support

Property Extraction Issues (Solved in v2.2)

Problem: Many nodes had empty properties/operations arrays.

Solution: Created dedicated PropertyExtractor class that handles:

1. Instance-level property extraction
2. Versioned node support
3. Both programmatic and declarative styles
4. Complex nested property structures

Dependency Update Issues (Solved in v2.3.3)

Problem: n8n packages have interdependent version requirements. Updating them independently causes version mismatches.

Solution: Implemented smart dependency update system:

1. Check n8n's required dependency versions
2. Update all packages to match n8n's requirements
3. Validate database after updates
4. Fix node type references in validation script

Technical Details:

• scripts/update-n8n-deps.js - Smart dependency updater
• .github/workflows/update-n8n-deps.yml - GitHub Actions automation
• renovate.json - Alternative Renovate configuration
• Fixed validation to use 'nodes-base.httpRequest' format instead of 'httpRequest'

AI-Optimized Tools (NEW in v2.4.0)

Problem: get_node_info returns 100KB+ of JSON with 200+ properties, making it nearly impossible for AI agents to efficiently configure nodes.

Solution: Created new tools that provide progressive disclosure of information:

1. get_node_essentials - Returns only the 10-20 most important properties
2. search_node_properties - Find specific properties without downloading everything

Results:

• 95% reduction in response size (100KB → 5KB)
• Only essential and commonly-used properties returned
• Includes working examples for immediate use
• AI agents can now configure nodes in seconds instead of minutes

Technical Implementation:

• src/services/property-filter.ts - Curated essential properties for 20+ nodes
• src/services/example-generator.ts - Working examples for common use cases
• Smart property search with relevance scoring
• Automatic fallback for unconfigured nodes

Usage Recommendation:

# OLD approach (avoid):
get_node_info("nodes-base.httpRequest")  # 100KB+ response

# NEW approach (preferred):
get_node_essentials("nodes-base.httpRequest")  # <5KB response with examples
search_node_properties("nodes-base.httpRequest", "auth")  # Find specific options

Docker Build Optimization (NEW in v2.4.1)

Problem: Docker builds included n8n dependencies (1.3GB+) even though they're never used at runtime, resulting in 12+ minute builds and 1.5GB images.

Solution: Removed ALL n8n dependencies from Docker runtime:

1. Database is always pre-built locally before deployment
2. Docker image contains only runtime dependencies (MCP SDK, SQLite, Express)
3. Separate package.runtime.json for clarity

Results:

• 82% smaller images (280MB vs 1.5GB)
• 10x faster builds (1-2 minutes vs 12+ minutes)
• No version conflicts - n8n updates don't affect runtime
• Better security - minimal attack surface

Technical Implementation:

• Dockerfile builds TypeScript without n8n dependencies
• Uses package.runtime.json with only 5 runtime dependencies
• Pre-built nodes.db (11MB) contains all node information
• BuildKit cache mounts for optimal layer caching

Build Process:

# Rebuild database locally (requires n8n)
npm run rebuild

# Build ultra-optimized Docker image
./scripts/build-optimized.sh

# Deploy (no n8n deps in container!)
docker compose up -d