Better every day. Proven in public.
The Lumen Index is the public composite behind every tier — reasoning, coding, knowledge, 中文 quality, and speed, tracked from real production duels. This is the trajectory, published as it happens, not a benchmark screenshot.
01 · The trajectory
Every tracked model, since its first measurement
One line per model. Gaps in slope are real — a day a run didn't reach that model, never smoothed away.
02 · Components
Five components, one number
The Index is a composite. Each of these is judged and tracked in its own right before they combine into the single number on the chart above.
Reasoning
Multi-step, hard-to-verify problems — judged on whether the reasoning holds up, not just whether the final line looks right.
Coding
Real coding tasks, judged on correctness and quality — not whether it merely compiles.
Knowledge
Breadth and accuracy of what the model actually knows.
中文
Chinese-language quality, judged as its own component — never assumed from English performance.
Speed
Real responsiveness in production, not an advertised token rate.
03 · Cadence
Two cadences, one trajectory
A lighter run and a deeper run keep the line moving without either one dominating it.
A lighter run happens daily, rotating its sample so coverage broadens over time — no single day tries to be a mega-run. A deeper run happens weekly, over a larger, fixed sample, and anchors the trend the daily runs trace between two deep readings.
Both run exactly like everything else in this system: sampled production traffic, judged off the serving path, at no cost to you. See Methodology for how a single duel actually works.
04 · The anchor
Fifty is a start, not a ceiling
Every model's index starts the same way, and moves only on evidence from there.
The first time a model completes a full five-component measurement, that run sets its baseline at 50. Not a hand-picked constant — whatever that model's own first real evidence works out to, normalized once, at that moment, and never recomputed afterward.
From there, the index moves however the evidence moves it. There is no ceiling: sustained, genuine improvement can carry a model's index past 100 over time.
Fifty is a starting line, not a scale limit.
05 · Confidence
What the shaded band means
Every point on the chart carries a range, not just a headline number.
The shaded band around each point is how sure that measurement is — not decoration. A wide band means the evidence behind that point is thinner, or the result closer to a toss-up; a narrow band means it's well-established.
Production duels don't produce a perfectly even amount of evidence every single day, so the band says that honestly instead of hiding it behind one clean line.
06 · Certification
The ladder is a hypothesis, not doctrine
Tier order isn't asserted once and left alone. It's checked continuously against production evidence.
Win-rate monotonicity
Judged head-to-head comparisons on real production traffic must show Flash ≤ Standard ≤ Pro ≤ Ultra in answer quality, region by region of the request space. A tier holds its slot only while it separates.
Merge on non-separation
If two adjacent tiers fail to separate beyond noise for a full evaluation window, the tier count is wrong and the tiers merge. Four is a hypothesis the data must keep earning, not doctrine.
This page is the evidence trail. For the mechanism that produces it — shadow duels, position-swapped judging, promotion gates, and automatic rollback — see Methodology. Or compare all four tiers side by side on Models.