toon/benchmarks/results/accuracy/report.md

Retrieval Accuracy

Tested across 2 LLMs with data retrieval tasks:

gpt-5-nano
  toon         ███████████████████░  97.5% (155/159)
  markdown-kv  ███████████████████░  95.6% (152/159)
  yaml         ███████████████████░  94.3% (150/159)
  json         ███████████████████░  93.7% (149/159)
  csv          ███████████████████░  93.7% (149/159)

claude-haiku-4-5
  markdown-kv  ███████████████░░░░░  76.7% (122/159)
  toon         ███████████████░░░░░  75.5% (120/159)
  json         ███████████████░░░░░  75.5% (120/159)
  csv          ███████████████░░░░░  75.5% (120/159)
  yaml         ███████████████░░░░░  74.8% (119/159)

Tradeoff: TOON achieves 86.5% accuracy (vs JSON's 84.6%) while using 46.3% fewer tokens.

View detailed breakdown by dataset and model

Performance by Dataset

Uniform employee records (TOON optimal format)

Format	Accuracy	Tokens	Correct/Total
toon	86.2%	2.483	100/116
csv	80.2%	2.337	93/116
yaml	82.8%	4.969	96/116
markdown-kv	84.5%	6.270	98/116
json	84.5%	6.347	98/116

E-commerce orders with nested structures

Format	Accuracy	Tokens	Correct/Total
toon	90.9%	5.967	80/88
csv	90.9%	6.735	80/88
yaml	89.8%	7.328	79/88
markdown-kv	90.9%	9.110	80/88
json	89.8%	9.694	79/88

Time-series analytics data

Format	Accuracy	Tokens	Correct/Total
csv	87.9%	1.393	51/58
toon	86.2%	1.515	50/58
yaml	86.2%	2.938	50/58
json	87.9%	3.665	51/58
markdown-kv	86.2%	3.779	50/58

Popular GitHub repositories

Format	Accuracy	Tokens	Correct/Total
csv	80.4%	8.513	45/56
toon	80.4%	8.745	45/56
yaml	78.6%	13.129	44/56
markdown-kv	82.1%	15.436	46/56
json	73.2%	15.145	41/56

Performance by Model

gpt-5-nano

Format	Accuracy	Correct/Total
toon	97.5%	155/159
markdown-kv	95.6%	152/159
yaml	94.3%	150/159
json	93.7%	149/159
csv	93.7%	149/159

claude-haiku-4-5

Format	Accuracy	Correct/Total
markdown-kv	76.7%	122/159
toon	75.5%	120/159
json	75.5%	120/159
csv	75.5%	120/159
yaml	74.8%	119/159

Methodology

• Semantic validation: LLM-as-judge validates responses semantically (not exact string matching).
• Token counting: Using gpt-tokenizer with o200k_base encoding.
• Question types: Field retrieval, aggregation, and filtering tasks.
• Real data: Faker.js-generated datasets + GitHub repositories.