Which integrations are available for this server?

Allows converting XML data into the compact Token-Oriented Object Notation (TOON) format, optimized for reducing LLM token consumption and costs. Enables the conversion of YAML data into the compact TOON format, significantly reducing the token footprint for large datasets sent to LLMs.

How do I use TOON MCP Server?

1. Click on "Install Server". 2. Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state. 3. In the chat, type @ followed by the MCP server name and your instructions, e.g., "@TOON MCP Server Encode this JSON list of orders into TOON to save tokens" That's it! The server will respond to your query, and you can continue using it as needed. Here is a step-by-step guide with screenshots.

TOON MCP Server

npm version License: MIT

MCP (Model Context Protocol) server for TOON (Token-Oriented Object Notation) encoding. Reduce LLM token usage by 50-70% when sending structured data.

What is TOON?

TOON is a compact data format optimized for LLM input. Instead of repeating field names for every object, it uses a header-based format:

JSON (1041 tokens):

[ {"id": 1, "name": "Product A", "price": 99.99}, {"id": 2, "name": "Product B", "price": 149.99} ]

TOON (389 tokens):

[id,name,price] 1,Product A,99.99 2,Product B,149.99

Result: 62% fewer tokens = 62% cost savings

Installation

Quick Start (npx - no install needed)

Add to your MCP settings:

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json):

{ "mcpServers": { "toon": { "command": "npx", "args": ["-y", "toon-mcp-server"] } } }

Claude Code (~/.claude/settings.json):

{ "mcpServers": { "toon": { "command": "npx", "args": ["-y", "toon-mcp-server"] } } }

Global Install

npm install -g toon-mcp-server

Then add to your MCP settings:

{ "mcpServers": { "toon": { "command": "toon-mcp" } } }

As Claude Code Skill

# Download the skill curl -o ~/.claude/skills/toon.md https://raw.githubusercontent.com/elminson/toon-mcp/main/skills/toon.md

Then use /toon in Claude Code.

Available Tools

`toon_encode`

Convert data to TOON format.

Supported formats: JSON, CSV, TSV, XML, HTML tables, YAML

Input: [{"name":"Alice","age":30},{"name":"Bob","age":25}] Output: [name,age] Alice,30 Bob,25

`toon_decode`

Convert TOON back to JSON.

`toon_analyze`

Analyze data and show potential token/cost savings.

`toon_optimize_prompt`

Find data sections in a prompt and convert them to TOON automatically.

Usage Examples

In Claude Desktop/Code (with MCP)

Just ask Claude to use the tools:

"Encode this JSON to TOON: [...]"
"Analyze how much I'd save converting this data to TOON"
"Optimize this prompt for token efficiency"

Programmatic (Node.js)

const { ToonEncoder } = require('toon-mcp-server/src/toon-encoder'); // Encode const data = [ { id: 1, name: 'Test', price: 99.99 }, { id: 2, name: 'Test 2', price: 149.99 }, ]; const toon = ToonEncoder.encode(data); // Get stats const json = JSON.stringify(data); const stats = ToonEncoder.getStats(json, toon); console.log(stats.savings.percent); // "64.5%" // Decode const decoded = ToonEncoder.decode(toon);

Benchmarks

Tested with OpenAI GPT-4o-mini:

Dataset Size	JSON Tokens	TOON Tokens	Savings
5 items	383	192	49.9%
20 items	1,394	530	62%
50 items	3,412	1,204	64.7%
100 items	6,800	2,400	~65%

Cost Savings at Scale

Volume	GPT-4o-mini	GPT-4o	Claude Sonnet
1M requests	$489 saved	$8,158 saved	$9,789 saved
10M requests	$4,890 saved	$81,580 saved	$97,890 saved

When to Use TOON

✅ Best for:

Arrays of objects with same structure (tables, lists, records)
API responses, database results
Large datasets sent to LLMs
Cost optimization at scale

⚠️ Less effective for:

Deeply nested, non-uniform data
Small payloads (<5 items)
Data with many unique field structures

Contributing

Pull requests welcome! Please open an issue first to discuss changes.

License

MIT

Install Server

A

security – no known vulnerabilities

A

license - permissive license

A

quality - confirmed to work

How are these scores calculated?

Resources

GitHub Repository

Need Help?

Report Issue

Related Servers

TOON MCP Server

TOON MCP Server

What is TOON?

Installation

Quick Start (npx - no install needed)

Global Install

As Claude Code Skill

Available Tools

`toon_encode`

`toon_decode`

`toon_analyze`

`toon_optimize_prompt`

Usage Examples

In Claude Desktop/Code (with MCP)

Programmatic (Node.js)

Benchmarks

Cost Savings at Scale

When to Use TOON

Contributing

License

Resources

Tools

New MCP Servers

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