GoTOON is a Go library implementing Token-Oriented Object Notation (TOON), a compact data serialization format designed to reduce token costs when passing structured data to Large Language Models. It achieves 30-60% token reduction compared to JSON by using tabular arrays, minimal syntax, and indentation-based structure while maintaining LLM comprehension. The library provides a Go-idiomatic API with functional options for customization including indent size, delimiters, and length markers.