June 3, 2026 · Yunus Emre Vurgun

Using TOON Format Efficiently with LLMs

toon · llm · prompting · tokens · api

TOON was created because LLMs spend a surprising number of tokens on JSON syntax. For reference material that is mostly keys and short values, a lighter notation wins.

Requesting TOON

GET /api/dataset/http-status-codes-complete?format=toon

Or directly from static files:

/static-data/dataset/http-status-codes-complete.toon

Prompt Tips

  • Prefer TOON for large lookup tables and comparison matrices.
  • Fall back to JSON only when you need to round-trip or mutate the data in the same context.
  • Always include the exact source URL in your system prompt for attribution and freshness.

YJTOON datasets are intentionally narrow and high-signal. They work best as grounding material rather than broad RAG corpora.