n8n Workflow Builder

# 📖 n8n Workflow Builder - Examples & Use Cases Concrete examples of how to use the MCP Server! 🎯 ## 🎬 Scenario 1: Create API Endpoint ### What you want: REST API endpoint that validates user data and saves it to Postgres ### How to do it: **You ask Claude:** ``` "I need an n8n workflow for an API endpoint. The endpoint should: - Receive POST requests - Validate user data (name, email, age) - Save to Postgres - Return success/error response" ``` **Claude uses:** `suggest_workflow_nodes` + `generate_workflow_template` **You get:** ```markdown # Workflow: User Registration API ## Suggested Structure: 1. **Webhook** - Receives POST requests - Path: /api/users/register - Authentication: Header Auth recommended 2. **IF Node** - Validation: email present? - Validation: age > 18? - True → continue, False → Error Response 3. **Set Node** - Format data for DB - Add timestamp - Sanitize inputs 4. **Postgres Node** - INSERT INTO users - Handle duplicates 5. **Respond to Webhook** - Success: 201 Created - Error: 400 Bad Request ## Best Practices: - Enable Webhook Authentication! - Input sanitization against SQL Injection - Use prepared statements - Return proper HTTP Status Codes ``` --- ## 🎬 Scenario 2: Daily Report ### What you want: Every day at 9 AM fetch sales metrics from DB and send via Slack ### How to do it: **You ask Claude:** ``` "Create a workflow that runs daily at 9 AM and: - Fetches sales data from Postgres (last 24h) - Calculates metrics (total revenue, orders, avg order value) - Formats as nice report - Sends via Slack to #sales-team" ``` **Claude uses:** `generate_workflow_template` (Type: `scheduled_report`) **You get:** ```markdown # Workflow: Daily Sales Report ## Template: Daily Report Generator 1. Schedule Trigger (Daily at 9AM) - Cron: 0 9 * * * - Timezone: Europe/Berlin 2. Postgres (Fetch Data) - Query: SELECT * FROM orders WHERE created_at > NOW() - INTERVAL '24 hours' - Return data as JSON 3. Function (Calculate Metrics) ```javascript const orders = $input.all(); const total_revenue = orders.reduce((sum, o) => sum + o.amount, 0); const order_count = orders.length; const avg_value = total_revenue / order_count; return [{ json: { revenue: total_revenue, orders: order_count, avg_order: avg_value } }]; ``` 4. Set (Format Report) - message: "📊 Daily Sales Report\n💰 Revenue: {{$json.revenue}}€\n..." 5. Slack (Send to Slack) - Channel: #sales-team - Message: {{$json.message}} ## Best Practices: ✅ Add error handling! ✅ Notify admin on errors ✅ Mind the timezone! ``` --- ## 🎬 Scenario 3: Debug Workflow ### What you have: Workflow throws error "Error: getaddrinfo ENOTFOUND api.example.com" ### How to solve it: **You ask Claude:** ``` "My workflow throws this error: 'Error: getaddrinfo ENOTFOUND api.example.com' The HTTP Request Node cannot reach the API." ``` **Claude uses:** `debug_workflow_error` **You get:** ```markdown # Workflow Error Debug ## Probable Cause: DNS/Network Error The error "getaddrinfo ENOTFOUND" means the hostname cannot be resolved. **Possible Causes:** 1. **URL Typo** - Check: Is "api.example.com" spelled correctly? - Common mistake: https://api.example.com vs http:// 2. **Network/Firewall** - Can n8n access external APIs? - Proxy config needed? - Firewall rule blocking traffic? 3. **DNS Problem** - Is the domain name valid? - DNS server reachable? **Solution Steps:** 1. Test in browser: Open https://api.example.com 2. Check URL in HTTP Request Node (typos?) 3. Test with curl: `curl https://api.example.com` 4. Check n8n network settings 5. For self-hosted: Check Docker networking **Quick Fix:** - Use IP address instead of hostname (temporary) - Check n8n logs: Settings > Log Streaming ``` --- ## 🎬 Scenario 4: Optimize Workflow ### What you have: Existing workflow that is slow and has many nodes ### How to improve it: **You ask Claude:** ``` "Analyze my workflow 'Customer Onboarding' (ID: abc-123) and give me optimization suggestions" ``` **Claude uses:** `analyze_workflow` **You get:** ```markdown # Workflow Analysis: Customer Onboarding **Complexity:** High **Total Nodes:** 23 ## ⚠️ Issues Found: - Node 'HTTP Request 3' contains hardcoded API key - Node 'Set 1' contains hardcoded password - No error handling detected ## 💡 Suggestions: - Consider splitting into sub-workflows (23 nodes is complex!) - Rename default node names: HTTP Request, Set, IF - Add Error Trigger node for better error handling - Move credentials to n8n Credential Manager - Consider batching HTTP requests ## 🚀 Optimization Plan: 1. **Security First:** - Move ALL credentials to Credential Manager - Never hardcode API keys/passwords 2. **Split Workflow:** - Main Flow: "Customer Onboarding - Main" - Sub-Workflow 1: "Send Welcome Email" - Sub-Workflow 2: "Setup User Account" - Sub-Workflow 3: "Notify Teams" 3. **Performance:** - Batch HTTP requests where possible - Use Redis for caching - Reduce sequential dependencies 4. **Maintainability:** - Rename all nodes meaningfully - Add notes/documentation - Use consistent naming scheme ``` --- ## 🎬 Scenario 5: Learn Node ### What you want: Understand how to properly use the Redis Node ### How to do it: **You ask Claude:** ``` "Explain the Redis node with use cases and best practices" ``` **Claude uses:** `explain_node` **You get:** ```markdown # Redis Node **Description:** Redis key-value store integration for caching, session storage and rate limiting ## Use Cases: - **Caching**: Cache API responses for better performance - **Rate Limiting**: Limit user requests - **Session Storage**: Store user sessions - **Temporary Data**: Store data with TTL - **Pub/Sub**: Message queue for event-based workflows ## Best Practices: ✅ **Always set TTL** - Prevents memory overflow - Automatic cleanup ```javascript key: "user:123" value: {...} ttl: 3600 // 1 hour ``` ✅ **Use appropriate data types** - String: Simple values - Hash: Object data - Set: Unique lists - Sorted Set: Ranked data ✅ **Error Handling** - Redis connection can fail - Implement fallback logic - Log Redis errors ✅ **Key Naming Convention** - Use prefixes: "user:123", "cache:api:endpoint" - Hierarchical: "app:feature:entity:id" - Stay consistent! ## Example: API Response Caching ```javascript // Check cache first GET key: "cache:api:users:{{$json.userId}}" // If miss → fetch from API → cache result SET key: "cache:api:users:{{$json.userId}}" value: {{$json}} ttl: 600 // 10 minutes ``` ## Common Pitfalls: ❌ No TTL → Memory full ❌ Too long TTLs → Stale data ❌ No connection error handling ❌ Keys without structure → Chaos ``` --- ## 🎬 Scenario 6: Smart Workflow Update ### What you want: Update a single node in an existing workflow without losing other nodes ### How to do it: **You ask Claude:** ``` "Update the 'API Handler' workflow - change the HTTP Request node URL to https://api.example.com/v2" ``` **Claude uses:** `update_workflow` (with smart merge) **What happens:** ```markdown # Smart Merge in Action Before (v1.13.1 and earlier - BUGGY): - Updating one node would OVERWRITE the entire workflow - All other nodes would be DELETED - Data loss! After (v1.13.2 and later - FIXED): - Only the HTTP Request node is updated - All other nodes remain untouched - Connections preserved - Safe updates! ## The Fix: ✅ Nodes are merged by name ✅ Only specified fields are updated ✅ New nodes can be added ✅ Existing nodes stay intact ``` **Result:** ``` Workflow Updated Successfully ID: abc123 Name: API Handler Nodes: 5 (unchanged) Changes Applied: - nodes: Updated structure (HTTP Request node URL changed) ``` --- ## 🎬 Scenario 7: Delete Test Workflows ### What you want: Clean up test workflows from your n8n instance ### How to do it: **You ask Claude:** ``` "List all workflows with '[TEST]' in the name and delete them" ``` **Claude uses:** `list_workflows` + `delete_workflow` **What happens:** ```markdown # Found 3 test workflows: 1. [TEST] API Endpoint - ID: abc123 2. [TEST] Daily Report - ID: def456 3. [TEST] Data Sync - ID: ghi789 # Deleting workflows... Workflow Deleted Successfully ID: abc123 Name: [TEST] API Endpoint ⚠️ The workflow has been removed from n8n. Workflow Deleted Successfully ID: def456 Name: [TEST] Daily Report ⚠️ The workflow has been removed from n8n. Workflow Deleted Successfully ID: ghi789 Name: [TEST] Data Sync ⚠️ The workflow has been removed from n8n. ✅ All test workflows cleaned up! ``` **Important Notes:** - Deletion may be irreversible depending on n8n config - Always backup important workflows first - Audit trail is logged in session state --- ## 🎬 Scenario 8: Template Recommendations ### What you want: Find the perfect template for your use case ### How to do it: **You ask Claude:** ``` "Recommend templates for building a customer notification system" ``` **Claude uses:** `recommend_templates` (Intelligent Template System v2.0) **You get:** ```markdown # Template Recommendations ## 1. Email Campaign Workflow (Score: 0.92) **Category:** Marketing **Difficulty:** Intermediate **Why this matches:** - Designed for customer notifications - Email + Slack + SMS support - Personalization features - Scheduling capabilities **Use cases:** - Product announcements - Order confirmations - Promotional campaigns ## 2. Event-Driven Notifications (Score: 0.88) **Category:** Automation **Difficulty:** Advanced **Why this matches:** - Real-time customer alerts - Multiple channels (email, SMS, push) - Webhook-triggered - Priority queuing **Use cases:** - Order status updates - System alerts - Transaction confirmations ## 3. Scheduled Report Sender (Score: 0.75) **Category:** Reporting **Difficulty:** Beginner **Why this matches:** - Regular customer communication - Email distribution - Data visualization - Time-based triggers ``` --- ## 🎯 Power Combos ### Combo 1: Create + Analyze workflow ``` 1. "Generate workflow for XYZ" 2. → Build workflow in n8n 3. "Analyze workflow ABC" 4. → Implement optimizations ``` ### Combo 2: Learn node + Generate template ``` 1. "Explain Postgres node" 2. → Learn best practices 3. "Generate template with Postgres + Slack" 4. → Get optimal workflow ``` ### Combo 3: Error → Debug → Fix ``` 1. Workflow fails 2. "Debug error: [Error Message]" 3. → Get solution 4. → Implement fix 5. "Analyze workflow again" 6. → Confirm fix works ``` ### Combo 4: Template → Customize → Deploy ``` 1. "Recommend templates for notification system" 2. → Choose best match 3. "Update workflow - add SMS node after email" 4. → Smart merge keeps structure 5. "Validate workflow before deployment" 6. → Deploy with confidence ``` ### Combo 5: Cleanup Workflow ``` 1. "List all workflows" 2. → Find unused/test workflows 3. "Delete workflow [TEST] API" 4. → Clean up workspace 5. "Show remaining workflows" 6. → Confirm cleanup ``` --- ## 💡 Pro Tips from Practice ### Tip 1: Iterative Design ``` Start: "Suggest nodes for: Daily Report" → Get outline → Refine details: "Explain Postgres Node" → Generate template: "Create complete workflow" → After building analyze: "Analyze workflow" ``` ### Tip 2: Template as Base ``` Use templates as starting point: "Generate scheduled_report template for Sales Metrics" → Adapt to your needs → Extend with custom logic ``` ### Tip 3: Security Check before Production ``` Before deployment ALWAYS: "Analyze workflow XYZ for security issues" → Fix hardcoded credentials → Add authentication → Check input validation ``` --- **Happy Building! 🚀** More questions? Just ask Claude! 😉