Rewrite · 6 checks · max 400 tokens · benched 2026-09-16

Kimi K3 vs Kimi K2.7 Code vs Kimi K2.6 vs Kimi K2.5 on jargon to plain english for a 12-year-old

Moonshotai models side by side on "Jargon to plain English for a 12-year-old": Kimi K2.7 Code scores 9/10; Kimi K2.7 Code is the cheapest answer scoring 8+ at $1.05 per 1,000 runs. Outputs, checks, judge reasons, latency and cost.

The prompt every model received

User

Rewrite this paragraph so a 12-year-old would understand it. Keep it under 70 words and do not use the words "leverage", "synergy" or "paradigm". Output only the rewritten paragraph.

Paragraph: Our next-generation battery architecture leverages a solid-state electrolyte paradigm to achieve synergy between energy density and thermal stability, enabling a 40% increase in range while mitigating the combustion risk profile associated with legacy lithium-ion chemistries.

Rubric for the judge: Simple vocabulary, keeps the 40% range gain and the safety point, under 70 words, banned words absent.

Side by side

Every cell is one OpenRouter call at temperature 0 with the prompt's token cap and reasoning effort "low" where the model supports it. Cost is usage × the catalogue rate in models.json. Quality is one judge call to anthropic/claude-haiku-4.5 against the prompt's rubric, cached per prompt version.

Kimi K3

moonshotai/kimi-k3

9/10

Latency: 815ms
Cost: $0.00360
Per 1,000: $3.60

216 in · 269 out (207 reasoning) · 45 words · checks 6/6

max_words
contains
contains
not_contains
not_contains
not_contains

Our new battery uses a solid inner layer instead of liquid, so it can store more energy without getting too hot. That means cars can go about 40% farther on one charge, and the battery is less likely to catch fire than older lithium-ion ones.

Judge: Excellent simplification for a 12-year-old, includes the 40% range gain and safety benefit, stays well under 70 words (42 words), avoids all banned words, and uses clear vocabulary.

Kimi K2.7 Code

moonshotai/kimi-k2.7-code

9/10

top judge scorecheapest scoring 8+

Latency: 322ms
Cost: $0.00105
Per 1,000: $1.05

100 in · 280 out (237 reasoning) · 36 words · checks 6/6

max_words
contains
contains
not_contains
not_contains
not_contains

Our new battery uses solid materials instead of liquid, so it holds more energy and stays cooler. This lets electric cars go 40% farther and makes them less likely to catch fire than older lithium-ion batteries.

Judge: Excellent rewrite: simple vocabulary, includes 40% range gain and safety benefit, 28 words (well under 70), avoids all banned words, and is perfectly understandable to a 12-year-old.

Kimi K2.6

moonshotai/kimi-k2.6

9/10

Latency: 736ms
Cost: $0.00150
Per 1,000: $1.50

100 in · 350 out (358 reasoning) · 43 words · checks 6/6

max_words
contains
contains
not_contains
not_contains
not_contains

 Our new battery uses solid materials instead of liquid inside, so it stores more power and stays cooler. This lets electric cars go 40% farther on one charge, and it's much safer because it won't catch fire as easily as older lithium batteries.

Judge: Excellent rewrite: simple vocabulary, includes 40% range gain and safety benefits, avoids all banned words, and is 48 words (well under 70-word limit); only minor issue is 'catch fire' could be slightly more precise than original 'combustion risk.'

Kimi K2.5

moonshotai/kimi-k2.5

9/10

Latency: 943ms
Cost: $0.00112
Per 1,000: $1.12

100 in · 479 out (437 reasoning) · 37 words · checks 6/6

max_words
contains
contains
not_contains
not_contains
not_contains

Our new battery uses solid materials instead of liquid chemicals. This lets electric cars go 40% farther on one charge. It also makes the battery much safer and less likely to catch fire than older lithium batteries.

Judge: Excellent rewrite: simple vocabulary, includes 40% range gain and safety benefit, 39 words (well under 70), avoids all banned words, and is perfectly understandable to a 12-year-old.

Frequently asked

What does this prompt test?

Rewrite: Simple vocabulary, keeps the 40% range gain and the safety point, under 70 words, banned words absent. The deterministic checks are max_words, contains, contains, not_contains, not_contains, not_contains.

Which model should I pick for this task?

If the judge's bar of 8/10 is good enough for you, Kimi K2.7 Code at $1.05 per 1,000 runs. If you need the top score, Kimi K2.7 Code at $1.05 per 1,000 runs.

Same prompt, other families

Run it yourself

Re-run this prompt on Moonshotai with your own OpenRouter key, or tweak the wording and see what changes.

Side by side

Kimi K3

Kimi K2.7 Code

Kimi K2.6

Kimi K2.5

Frequently asked

Same prompt, other families

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