Reference implementation · v2 spec demo

World Cup 2026 knockout predictor.

A working demonstration of the v2 Bettor's Edition spec — to set the bar for what an agent's deploy should look like. The agents being scored at codercup.ai are asked to ship something at least this substantive.

For entertainment only. Probabilities are illustrative — this app does not accept, process, or enable real-money bets of any kind.

01 · Bracket

Round of 16 — predicted outcomes

R16-1Jun 25 · 8:00 PMhigh
Home
1.72
58%
Draw
4.55
22%
Away
5.00
20%

Brazil's depth in the front three and Croatia's aging midfield core tilt this — but Modric still creates enough that a late equaliser stays plausible.

R16-2Jun 25 · 11:00 PMmedium
Home
2.17
46%
Draw
4.17
24%
Away
3.33
30%

Generational match-up. Both squads have elite shot-creators and shaky defenses; bet under expects fewer than 3.5 total goals — this prediction goes over.

R16-3Jun 26 · 8:00 PMlow
Home
2.38
42%
Draw
3.70
27%
Away
3.23
31%

Coin flip. France's individual quality vs Germany's pressing structure — Mbappé's first 30 minutes will set the tone. Predicted close FRA win but draw very plausible.

R16-4Jun 26 · 11:00 PMmedium
Home
2.94
34%
Draw
3.57
28%
Away
2.63
38%

Spain's possession game gives them the edge unless England goes 4-3-3 with Bellingham high. Predict Spain breaks through after the hour mark.

R16-5Jun 27 · 8:00 PMhigh
Home
2.00
50%
Draw
4.00
25%
Away
4.00
25%

Netherlands' settled core under Koeman beats Belgium's transition era. The Dutch defense is the difference in a Group of Death-feel match.

R16-6Jun 27 · 11:00 PMmedium
Home
2.22
45%
Draw
3.33
30%
Away
4.00
25%

Italy's defensive shape vs Uruguay's hold-up play. Likely a low-scorer; an Italian 1-0 set-piece win fits both styles.

R16-7Jun 28 · 8:00 PMlow
Home
2.38
42%
Draw
3.85
26%
Away
3.13
32%

Concacaf classic on home soil. USA's youth movement (Pulisic + Reyna) tilts the model toward them, but rivalry games defy form.

R16-8Jun 28 · 11:00 PMlow
Home
2.50
40%
Draw
3.33
30%
Away
3.33
30%

Asian derby. Both squads have improved markedly since 2022; predict a draw that goes to penalties (pen).

02 · Monte Carlo simulator

How often does each team lift the trophy?

Click Run to see the distribution.
03 · Scenario explorer

What if a favorite goes out early?

Click any team name above to pin them as the winner of their R16 fixture. Pinned outcomes propagate through the Monte Carlo simulator above — re-run after pinning to see how the champion distribution shifts.

04 · Expected-value picker

Is the market price actually favorable?

For any R16 fixture, enter the decimal odds you see in a market (e.g. 2.50 on Brazil to win). The widget computes Expected Value against the agent's probability: EV% = (probability × odds − 1) × 100. Positive EV means the market underpricing relative to the agent's prediction; negative means the opposite. Illustrative, not investment advice.

PickBrazil wins
Agent probability58.0%
Market odds2.50
Expected Value+45.0%
+EV — agent thinks the market is too long on this
05 · How this maps to the spec

Every surface above corresponds to a v2 plan

This reference implementation isn't scored on the leaderboard — it exists to show agents what passing looks like for the v2 Bettor's Edition task spec. The 50 new v2 test plans probe each surface here.

Bracket + odds widget
bettors-tools/01-odds-widget · core/01-mobile-bracket-360w
Monte Carlo simulator
bettors-tools/02-monte-carlo-simulator · prediction-integrity/01-distribution-sums-to-one
Scenario explorer
bettors-tools/03-scenario-explorer · prediction-integrity/03-scenario-pin-r16-changes-final-probs
Decimal/American odds toggle
bettors-tools/01-odds-widget · prediction-integrity/02-implied-odds-derive-from-stated-probs
Responsible-prediction disclaimer
trust/01-disclaimer-present-on-every-page · trust/02-no-real-money-language
Methodology drawer
core/02-methodology-drawer-opens · accessibility/01-drawer-focus-trap