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Ground truth

Every reference tuple in this benchmark comes from the game itself — a replay parser or a pinned engine — never from a human annotator and never from a model. That is the property that makes the corpus extensible: a new held-out case costs compute, not labelling, so the 20 published cases per environment can be refreshed without renegotiating what a label means.

Two mechanisms:

How VtV_t is obtained Environments
Parser the game already computes the quantity; the adapter reads it out of the replay, demo, trace, or annotation CS2, DOTA 2, SC2, GFootball, Badminton
Evaluator the game does not define a win probability, so a pinned engine supplies one for every prefix Go, Chess, Gomoku, Doudizhu

A parser environment has no engine to pin and no evaluator noise — score_after in GFootball is the engine's own score. An evaluator environment has to pin the engine and its search budget, because a win probability is only reproducible at a fixed configuration; those pins are listed per environment below.

Sources were last accessed 2026-09-04.


What every GT file contains

tasks/<game>/gt/<case_id>_gt.json

One file per case. The reference tuples live under events — the same root key in all nine games, and the same key an answer file uses — and each row carries T1's perception fields, T2's update label, and T3's resulting state side by side. Everything else in the file is provenance and is not scored: engine pins, thresholds, case type, per-class counts, audits.

Each file also carries a top-level _canary string. Please keep it: it is how contamination gets detected later, and it costs a training pipeline nothing to drop these files.

Row counts, which are also the strict-F1 denominators:

Game Cases Reference tuples per case
Go 20 5,516 276
CS2 20 3,703 185
Chess 20 1,761 88
SC2 20 1,358 68
Badminton 20 701 35
Gomoku 20 808 40
DOTA 2 20 597 30
Doudizhu 20 429 21
GFootball 20 405 20
Total 180 15,278

Two conventions that are easy to misread

A T1-only row is not a missing label. Go and Chess emit capture rows alongside move rows. A capture is a perception event with no VtV_t update of its own — the move that caused it already carries that — so its wr_swing and leader_after are null by design (378 of 5,516 rows in Go, 331 of 1,761 in Chess). Those rows are scored at T1 and excluded from the T2/T3 denominators.

Doudizhu abstains near a band boundary. A row whose label sits within 2σ of its band edge carries null on that tier and t2_unresolved / t3_unresolved set (79 rows at T2, 47 at T3, out of 429). The PIMC estimate cannot separate those from the other side of the band, so scoring them would be scoring sampling noise. The model cannot tell which rows those are and must answer every row — abstention removes undecidable labels from the numerator; it does not make the task easier.


T3 is not one metric

T3 asks the same question everywhere — where does this leave the match — but what counts as an answer follows the VtV_t of the environment:

T3 answer Metric Environments
a three-way class label macro accuracy Go, Chess, Gomoku, Doudizhu, DOTA 2, SC2
an exact integer score pair exact-pair accuracy GFootball, Badminton
the cumulative score pair after the round exact fraction CS2

score.py prints all three in one T3 column and each judge records which it computed. A class label where the score is the state would be a weaker question, and an exact pair where VtV_t is a win probability would be unanswerable.

T2's class vocabulary is not uniform either — it is whatever a change in that VtV_t can be: {A, B, equal} on a win probability, four classes (taken / extended / levelled / narrowed) on a score differential, two (T / CT) on a CS2 round. Chance level therefore differs by game: 0.333 on three classes, 0.25 on four, 0.5 on two. Every judge macro-averages over per-class recall precisely so a constant answer lands on chance instead of on the majority share — which on Go's T2 would otherwise read 0.87 (4,481 of the 5,138 labelled rows are equal).


Case stratification

Cases are not a random sample of matches. Each environment selects 20 from a larger pool so the corpus contains matches that are hard for different reasons, and so no single class dominates the T2/T3 labels. Eight of the nine environments stratify by trajectory shape, derived from the VtV_t trajectory itself:

  • blowout — one side ahead essentially throughout
  • tense — repeated lead changes
  • reversal (CS2 and DOTA 2 call it comeback) — the eventual winner trailed
Game blowout tense reversal / comeback
Go 5 10 5
Chess 3 11 6
Gomoku 6 10 4
Doudizhu 7 7 6
CS2 8 5 7
DOTA 2 7 6 7
GFootball 7 6 7
Badminton 6 7 7

SC2 is the exception and its CASE_TYPES.json carries no trajectory label: resource-equivalent value rarely reverses inside a game, so within one match leader_after is effectively two-class {leader, equal} and a reversal class would be empty. It balances on which side led instead — 10 A-led and 10 B-led — which is what keeps its dataset-pooled T3 from collapsing onto one class (A 568 / B 531 / equal 259 across 1,358 events).

The rule that assigns a trajectory type is per-environment, not shared. It depends on the shape of that VtV_t: a score-difference VtV_t makes reversal nearly impossible to detect from a trough (GFootball uses "winner ever trailed" plus a peak threshold), while a win-probability VtV_t makes blowout the fragile one (Doudizhu keys on the winner-perspective trough at 0.12 / 0.22). Always smooth before taking an extremum.

Six CASE_TYPES.json files carry numeric thresholds — Go, Chess, Gomoku, CS2, and DOTA 2 the stratification thresholds they used, SC2 its event-segmentation ones. Doudizhu carries the note that its thresholds are fixed across the corpus (re-tuning ε per case would stop macro accuracy being comparable between cases), and GFootball and Badminton record only the resulting distribution. All nine carry the per-case label (SC2's is leading_side). The VtV_t definition is in every game's instruction.md and in the per-environment sections below; CASE_TYPES.json repeats it for Doudizhu, GFootball, Badminton, and SC2.


Per environment

Go — board · evaluator

Source SGF records via the OGS public API, fixture game 27400000 — https://online-go.com
GT mechanism evaluator. The adapter replays each move and evaluates every prefix
Engine pin KataGo, network b18c384nbt, 1600 visits per position
\(V_t\) Black win probability, ±10 pp dead band around 0.50
Render plain 19×19 board, 612², 25 fps. No coordinates, move numbers, names, clocks, capture counters, komi, or evaluation bar

T1 is the move or capture with its time, colour, and board coordinate. T2 is the quantized signed change in Black's win rate caused by the move (wr_swing). T3 is the win-rate leader immediately after it (leader_after). Selection balances the winning colour 10 B / 10 W.

Go is the largest environment by tuples per case (276), so it is where a model's ability to hold a whole match in view is most exposed — and where Protocol A's frame grid bites hardest.

Chess — board · evaluator

Source public Lichess game export, fixture cZWtZEBE — https://lichess.org
GT mechanism evaluator, per-ply, with real per-ply timing
Engine pin Stockfish 18, depth 20, value function white_expected_score_wdl
\(V_t\) White-oriented expected score / WDL, ±10 pp band. Draws map to the neutral label
Render plain 8×8 board, 548², 1 fps. No coordinates, move numbers, names, clocks, result text, captured-piece tray, or evaluation bar

T1 records the destination square only, not the origin — the released contract is deliberately weaker than full move notation. T2 is the quantized change in the White-oriented value; T3 is the post-ply leader.

The video is natively 1 fps because a ply is a discrete event; Protocol A's sampler is clamped by the container rate, so it never asks ffmpeg to fabricate frames here.

Gomoku — board · evaluator

Source competition PSQ records (Gomocup)
GT mechanism evaluator
Engine pin Rapfi, 1000 ms per turn, freestyle rule, black_winrate_sigmoid_eval (scaling factor 200) — https://github.com/dhbloo/rapfi
\(V_t\) tempo-neutral smoothed Black win probability, ±10 pp band
Render plain 15×15 board, 504², 25 fps. No coordinates, move numbers, names, clocks, or engine annotations

Why the smoothing matters. Gomoku is attack-dominant, so a raw side-to-move win rate swings back and forth with whose turn it is — a square wave that has nothing to do with who is actually ahead. Left alone it turns "who leads" into "who moves next", which is a move-parity shortcut, readable off the stone count with no understanding of the position. The release applies v_smooth[t] = (v[t] + v[t-1]) / 2 (trailing2_movepair) to cancel it, then gates on terminal consistency. All 20 cases share that pin.

Doudizhu — card · evaluator

Source DouZero-WP greedy self-play deals (τ=0) — https://github.com/kwai/DouZero, weights at https://huggingface.co/palemoky/douzero-baselines
GT mechanism evaluator: hidden-hand PIMC — determinize, then roll out
Estimator adaptive 400–4000 worlds per state, greedy rollouts with the released DouZero-WP policy. The PIMC estimator is part of this benchmark, not a DouZero component
\(V_t\) landlord win probability = fraction of sampled deals the landlord wins. Bands: landlord > 0.55, farmers < 0.45, else equal. T2 impact ε = 0.034, T3 band = 0.05
Render tabletop, 1280×720, 24 fps. Landlord hand and the three bottom cards face up; farmer hands face down, showing only their counts. No numeric score, timer, move counter, or probability display

Hiding the farmer hands is what makes VtV_t non-degenerate. With every hand visible the value is close to a deterministic function of the cards, and the task collapses into card counting. The evaluator is given exactly the landlord's information set — own hand, the bottom three, all plays so far, and both farmer card counts — and samples uniformly from the deals consistent with it.

That leaves one shortcut worth naming, because it is the one a model will find: "whoever holds fewer cards is ahead." Card counts are public, so it is tempting. Measured over 9,954 events, it buys only +0.05–0.09 macro accuracy and is at its worst in the endgame — exactly when the landlord's hand is also small but the outcome runs the other way. Across this corpus it is capped at macro_acc ≤ 0.45.

T1 is every move that plays ≥1 card, with the player, combination type, and card count; passes are shown on screen but never reported. Each play occupies a 6 s display window and game_clock_s is its midpoint, so the ±3 s tolerance is exactly half a window — any time inside the window pairs up, with no ambiguity across plays.

Counter-Strike 2 — FPS · parser

Source public professional-match demo (.dem) files published on HLTV; the game is https://www.counter-strike.net
GT mechanism parser, our own, at the demo's native 64 Hz tick rate; positions resampled to 4 Hz for the render
\(V_t\) the cumulative round score, by persistent team (A / B) across the halftime side swap
Render clean top-down radar, 768², 15 fps, 1:1 real pace. Map geometry, player motion, bomb state, and event-relevant effects preserved; HUD, scoreboard, round counter, kill feed, economy, names, and audio removed

T1 covers six event types — kill, bomb_planted, bomb_defused, bomb_exploded, elimination, save — with their time and type-specific attributes. On a kill, the side and the dot number 1–10 identify the victim, not the killer, because the death marker is rendered without team colour or number. A kill row therefore carries side and number; the four conclusion types carry winner_side instead, and bomb_planted carries the planter's side.

T2 is the winner of the round containing the event; T3 is the cumulative score right after that round. Both are carried on every event row and are round-constant, rather than exposed as separate per-round fields.

The retained bomb/countdown corner clock is the only on-screen number in the whole corpus, and it is deliberate: it is the round timer, not the state.

score_after is cumulative, so its errors propagate. One early round mis-attributed shifts every later row's score_after, and because strict F1 voids a tuple on any wrong field, a single early mistake can cost the rest of the match. This is the intended difficulty — tracking means tracking — but read a near-zero CS2 strict F1 against its T1, which is scored independently.

20 cases: 8 blowout / 5 tense / 7 comeback, listed in tasks/cs2/CASE_TYPES.json.

DOTA 2 — MOBA · parser

Source Valve replays plus OpenDota match records — https://www.opendota.com, https://github.com/odota
GT mechanism parser (manta-based) for events, OpenDota's minute-level gold curve for the state
\(V_t\) the parsed net-worth advantage — explicitly not a learned win-probability model. even = within ±1000 gold
Render the real minimap terrain art with GT-anchored coordinates and real game sprites, 768², 15 fps. HUD, scoreboard, clock, net-worth graph, names, and objective counters removed

T1 covers six event types — first blood, teamfight, tower, barracks, Roshan, ancient — each with its own attributes (side, killer or winner, death counts, tier, lane, objective type). T2 quantizes the change in net-worth advantage over the aligned minute-level interval (minute_gain); T3 is the net-worth leader at that interval's end (leader_after).

Time axis. Every DOTA 2 video starts 8 s before the horn (video.preroll_s = 8.0, speed 1.0, in all 20 cases), so video_ts = max(0, game_s) + 8 and the event's minute is m = floor(max(0, video_ts − 8) / 60) — this reproduces the GT minute for all 597 events, where the older floor(video_ts / 60) agreed on only 521. Events the parser dates before the horn are clamped to the horn, video_ts = 8.0, even when they fall before the video's first frame (game second −8) — eight rows: first blood in dota-02/03/04/05/06/07, plus a pre-game teamfight in dota-04 and dota-06. The dota-04 teamfight (game second −47) carries deaths: 0 and winner_side: even; it is kept as the parser emitted it rather than edited by hand, so read a miss on that one row with this in mind.

Using the parsed gold curve rather than a win model is a deliberate choice: a learned win probability would make the reference depend on a model, and then the benchmark would be scoring agreement with that model rather than with the game.

Its T2/T3 macro is computed over matched events only (as is SC2's). Low T1 recall therefore shrinks the T2/T3 denominator and can delete the hard classes — especially equal — from it, so a T3 number backed by one surviving class is not comparable to one backed by three. The other seven judges count an unlocalized event as wrong instead. score.py prints T1 next to T2/T3 so the two can be read together.

DOTA 2 is the longest environment (47.8 ± 15.4 min), which is why its Protocol A recall ceiling is the lowest in the corpus at 0.597.

StarCraft II — RTS · parser

Source engine-generated AI-vs-AI replays (difficulty Harder, 6 matchups, 2017 ladder maps). Replay protocol: https://github.com/Blizzard/s2client-proto
GT mechanism parser — the replay tracker stream, read during a disable_fog god-view replay pass; deaths from raw dead_units (morph-free)
Engine SC2 4.10, base build 75689 (Blizzard Linux research build) via PySC2, rendered with EGL
\(V_t\) resource-equivalent advantage share s=(VA−VB)/(VA+VB)∈[−1,1]s=(V_A-V_B)/(V_A+V_B)\in[-1,1], band ±0.10. VV = banked minerals + gas, live army value, economy value, technology value
Render full-map isometric observer god-view, 1536², 5.6 fps, real time. Resource counters, production panels, minimap, names, and other direct readouts removed

T1 is a battle or building_destroyed event with its time and coarse map region: the playable area is quantized into a 3×3 grid written r{row}c{col}, so the label names the region a viewer would point at rather than a pixel. Thresholds: battles merge deaths within 2.5 s and need ≥150 resource value; a building death needs ≥80. T2 (fight_result) is the banded net army value traded; T3 (leader_after) is the banded share 3 s after the event resolves.

Because the source games are engine-generated they were never public, which makes this environment contamination-free by construction.

Each released case is ONE 1536² full-map video. The 3×3 tile_r{r}c{c}.mp4 files are internal to the render pipeline and are not part of the release — and the entity grid is a quantization of the playable area, not a reference to a video tile. Frames are captured every 4 game loops (≈0.18 s) so the ±3 s tolerance is physically achievable; the container fps is cosmetic, since event timing comes from the tracker stream.

GFootball — sports · parser

Source randomized Google Research Football simulator episodes (bot vs bot) — https://github.com/google-research/football
GT mechanism parser. Score transitions from the engine's obs['score']; the scorer name from the engine's own goal log
\(V_t\) left_goals - right_goals, the engine's native score. No evaluator
Render the engine's default inclined 3D broadcast view, full 1280×720, 24 fps, uncropped, real time (1 engine step = 1 frame)

T1 is the goal with its time, scoring side (L / R), scorer surname, and own-goal flag. T2 is the four-class score-differential change — taken, extended, levelled, narrowed — from the pre-goal difference. T3 is the exact score pair after the goal.

The HUD is suppressed inside the engine, in a patched wheel (GFOOTBALL_HIDE_HUD=1), not painted over afterwards. The minimap and the floating scorer-surname label above the ball carrier remain visible and are part of the released visual contract — the surname label is the only readable source for scorer_name.

Own goals are admitted rather than filtered, so scoring_side is the side that benefits, which is not always the side that touched the ball last.

Reading the scorer correctly took three attempts, and the two failures are instructive about trusting an engine field: ball_owned_player on the goal frame is -1 (nobody owns the ball at that instant), and "last owner" attributes a one-touch shot to the passer. The release reads the engine's own VA_GOAL_LOG line, pairs it in order, and fails rather than falls back if the score= in that line disagrees with the score chain.

Badminton — sports · parser

Source ShuttleSet stroke records (KDD-23) — https://github.com/wywyWang/CoachAI-Projects, https://arxiv.org/abs/2306.04948
GT mechanism parser: strokes grouped into points, the native score carried through each rally
\(V_t\) pts_near - pts_far within the set. No evaluator
Render fixed-camera synthetic 3D, 1280×720, 15 fps. A synthetic render built from real trajectories, not a source replay
Granularity one set of a singles match

T1 is the point with its time, scoring side (near / far, relative to the fixed camera), and the terminal landing zone — one of net, out, in_front, in_mid, in_back. T2 is the four-class score-differential change; T3 is the exact score pair after the point.

Two properties of this environment shape the task more than the schema does:

  • Two thirds of the video is dead time (dead_frac 0.54–0.72, mean 0.66). Between rallies the two figures simply walk to the next serving position. It looks exactly like live play apart from the shuttle not being struck, and there is no visual marker for the end of a rally — so the point boundary has to be read from the players' actions. Consecutive points are ≥13 s apart across all 681 intervals in the corpus, so a ±3 s window can never straddle two of them.
  • in_back is a 0.76 m band. All three dividing lines for the in_* classes are painted lines (the front service line and the doubles back service line, which is on the court even in singles). in_back is rare; answering it because a shot "looks deep" is wrong unless the shuttle actually crossed that line.

Because the renderer is synthetic, its HUD guarantee is structural rather than measured: this module never reads a score column, so no flag can turn one on, and no font is ever loaded, so there are no glyphs to render.

Licence notice travels with the data. ShuttleSet ships no LICENSE of its own; it inherits MIT (© 2022 Wei-Yao Wang) from the CoachAI-Projects repository root, which is what makes these derived renders redistributable. The full notice is in tasks/badminton/ATTRIBUTION.md and must accompany any redistribution.