Usage Guide

n8n expressions must be wrapped in double curly braces:

✅ Correct: {{$json.body.email}}
❌ Wrong:   $json.body.email

For webhook data, remember it's under .body:
{{$json.body.name}}     // Webhook form data
{{$json.body.message}}  // Webhook message

In Code nodes, use direct access (no {{}}):
const email = $json.body.email;  // Correct in Code node

To find the Slack node, use search_nodes:

search_nodes({query: "slack"})

This returns:
- nodeType: "nodes-base.slack"         (for search/validate tools)
- workflowNodeType: "n8n-nodes-base.slack" (for workflows)

⚠️ Important: Use different formats for different tools!

Next, get node details:
get_node({nodeType: "nodes-base.slack"})

This returns ~1-2K tokens with standard detail (default), covering 95% of use cases.

For webhook to Slack, use the Webhook Processing pattern:

Pattern Structure:
Webhook Trigger → [Transform] → Slack Notification

Workflow Checklist:
□ Search for nodes (search_nodes)
□ Get node configurations (get_node)
□ Create workflow structure
□ Add data mappings (expressions)
□ Validate workflow
□ Test with sample data

Real Example from Template #2947:
Webhook → OpenStreetMap → NWS → Slack
(1,500 views, proven pattern)

Validation Error: "Required field 'channel' missing"

Fix:
validate_node({
  nodeType: "nodes-base.slack",
  config: {
    resource: "message",
    operation: "post",
    channel: "#general",  // Add this!
    text: "Message"
  },
  profile: "runtime"
})

Auto-sanitization will fix:
✅ Binary operator structures (equals, contains)
✅ Unary operator structures (isEmpty, isNotEmpty)
✅ Missing metadata in IF/Switch nodes

But cannot fix:
❌ Broken connections
❌ Branch count mismatches

HTTP Request node property dependencies:

1. Set sendBody = true
   ↓ Reveals: contentType

2. Set contentType = "json"
   ↓ Reveals: specifyBody

3. Set specifyBody = "json"
   ↓ Reveals: jsonBody

This cascade of 32 dependencies ensures you see only relevant properties!

For AI workflows, 8 connection types:
- ai_languageModel (OpenAI, Anthropic)
- ai_tool (HTTP Request Tool, Code Tool)
- ai_memory (Window Buffer Memory)
- ai_outputParser, ai_embedding, ai_vectorStore...

In Code nodes, data access uses no {{}} syntax:

// Access all items
const items = $input.all();

// Access first item
const first = $input.first().json;

// For webhook data
const email = $input.first().json.body.email;

// Return format is always an array of objects
return [{
  json: {
    processed: true,
    email: email
  }
}];

⚠️ Python Code nodes have a critical limitation:
No external libraries (requests, pandas, numpy, etc.)

Use JavaScript for 95% of use cases.

If you must use Python, only standard library is available:
import json      # ✅ Available
import datetime  # ✅ Available
import re        # ✅ Available
import requests  # ❌ NOT available
import pandas    # ❌ NOT available