serde_toon

A Serde-compatible TOON serialization library for Rust.

What is TOON?

TOON (Token-Oriented Object Notation) is a compact format for LLMs, using 30-60% fewer tokens than JSON.

Example - Same data, different size:

// JSON (191 chars)
[
  {
    "id":1,
    "name":"Alice",
     "email":"alice@example.com",
     "active":true
  },
  {
    "id":2,
    "name":"Bob",
    "email":"bob@example.com",
    "active":true
  }
]

// TOON (83 chars - 56% smaller)
[2]{active,email,id,name}:
  true,alice@example.com,1,Alice
  true,bob@example.com,2,Bob

See examples/token_efficiency.rs

Quick Start

[dependencies]
serde_toon = "0.1"
serde = { version = "1.0", features = ["derive"] }

use serde::{Deserialize, Serialize};
use serde_toon::{to_string, from_str};

#[derive(Serialize, Deserialize)]
struct User { id: u32, name: String }

let user = User { id: 123, name: "Alice".into() };
let toon = to_string(&user)?;
let back: User = from_str(&toon)?;

Features

• Full Serde integration
• Zero-copy deserialization
• Comprehensive error messages
• Multiple array formats
• No unsafe code

Documentation

See https://docs.rs/serde_toon

License

MIT OR Apache-2.0