n8n-nodes-toon-json

n8n node to convert between JSON and TOON (Token-Oriented Object Notation)

This node converts between JSON and TOON (Token-Oriented Object Notation), a lightweight, human-readable, LLM-friendly format for structured data.

What is TOON?

TOON represents JSON in a compact, indentation-based text format:

• Objects become key: value lines
• Arrays of objects become pipe-separated tables
• Primitive arrays become comma-separated lists
• Nested structures are indented with 2 spaces

Example — JSON:

{
  "name": "Alice",
  "scores": [10, 20, 30],
  "address": {
    "city": "Berlin",
    "zip": "10115"
  }
}

Same data as TOON:

name: Alice
scores:
  10, 20, 30
address:
  city: Berlin
  zip: 10115

Array of objects becomes a table:

name | age | city
Alice | 30 | Berlin
Bob | 25 | Hamburg

Parameters

| Parameter | Type | Description | | ------------ | ------ | -------------------------------------------------------- | | Operation | Option | JSON to TOON or TOON to JSON. | | Input Field | String | Name of the field on the input item to read from. | | Output Field | String | Name of the field on the output item to write result to. |

Usage

JSON to TOON

Reads the value of Input Field from the input item, serialises it to TOON text, and writes the result to Output Field.

Useful for reducing token count when passing structured data to an AI/LLM node.

TOON to JSON

Reads the TOON string from Input Field, parses it back into a JSON object, and writes the result to Output Field.

Useful for deserialising LLM output back into structured data for downstream nodes.

Example Workflow

HTTP Request (fetch JSON data)
  → TOON Converter (JSON to TOON)
  → AI Agent / LLM node
  → TOON Converter (TOON to JSON)
  → Further processing

Authors

• sebse

License

This project is licensed under the AGPL-3.0-only License. See the LICENSE file for details.