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Smallest

lightning_v3.1

Measured 2026-07-03

Run lightning_v3.1 on Speko →

One API, every model on this board.

Naturalness

1544

Win % · 95% CI

58%

51–64%

Drift

det

Synth p50

173ms

173–193 p50–p90

Robustness

0.25

Fined:

• fatal · currency — dropped the minus sign (7 of 7 transcripts)

→ we sent “The balance is -$12.50.”

→ it said “The balance is $12.50.”

• fatal · math operators — never said “divided” (6 of 7 transcripts)

→ we sent “That is 100÷4=25 per person.”

→ it said “That is $134 equals 25 per person.”

• fatal · currency (international, ×0.4) — dropped the minus sign (7 of 7 transcripts)

→ we sent “Balance: -€45,90 outstanding.”

→ it said “Balance: 45 euros and 90 cents outstanding.”

+ 6 more fined

Not re-measured: v1.3 only (125 fixtures), score held at its last published value. Smallest refuses English from our account (LANGUAGE_NOT_ENABLED_IN_REGION), so the v1.4/v1.5 fixtures could not run, and re-scoring the old fine on the new curve (0.47) would rank an untested row above re-tested ones.

Cost / 1M chars

$17.5

Pay-as-you-go; $0.175/10k chars (smallest.ai/pricing/models).

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