toon-format/toon
🎒 Token-Oriented Object Notation (TOON) – Compact, human-readable, schema-aware JSON for LLM prompts. Spec, benchmarks, TypeScript SDK.
TOON helps developers working with Large Language Models (LLMs) by providing a more compact and readable way to format structured data inputs. It takes existing JSON data and translates it into a token-efficient format that LLMs can process reliably, reducing both cost and potential errors. This is primarily useful for AI/ML engineers and data scientists preparing data for LLM prompts.
23,207 stars. Used by 21 other packages. Actively maintained with 1 commit in the last 30 days. Available on npm.
Use this if you need to provide structured data, especially uniform lists or tables, to Large Language Models while minimizing token usage and improving the model's ability to parse information accurately.
Not ideal if your data is extremely complex with many nested levels, if you're working with purely tabular data where CSV is already sufficient, or if ultra-low latency is your absolute highest priority.
Stars
23,207
Forks
1,033
Language
TypeScript
License
MIT
Category
Last pushed
Mar 10, 2026
Commits (30d)
1
Reverse dependents
21
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