The robot followed its per-game playToWin/lose intent on every move, which made
the outcome too predictable. It now flips that intent for a single move on ~20%
of opening/midgame turns (a winning robot eases off, a losing one surges ahead),
so the chosen strategy may not pan out — which favours the human. The chance
tapers linearly to 0 over the last 14 tiles in the bag and is 0 once the bag is
empty, so the endgame follows the chosen strategy strictly.
The decision is deterministic from the seed (mix(seed,"deviate",moveCount)) and
applies to both robot paths via the shared selectMove; the per-game play-to-win
intent the admin card shows is unchanged. Adds deviateProb/deviates helpers and
unit tests (taper bounds + monotonicity, never-in-endgame, determinism, ~20%
distribution); bakes the behaviour into ARCHITECTURE §7, FUNCTIONAL (+_ru),
backend/README, PRERELEASE and PLAN Stage 5.
Two owner-reported defects from a live contour game.
A. Frequency: the robot's proactive nudge fired hourly for 12h+ (a 12h idle threshold
then the 1h cooldown, uncapped). Replaced with a lengthening, randomized schedule
(proactiveNudgeGap): the first nudge ~60-90 min into the human's turn, each later gap
growing toward 1-6h (uniform sample in [60min, ceil], ceil ramping 90min->6h over 12h
of idle, measured from the previous nudge), so a long wait gets a handful of
increasingly-spaced reminders instead of a stream.
B. Language: out-of-app push routed by the recipient's GLOBAL service_language
(last-login-wins), so after re-logging via the RU bot an English game's nudges came
from the RU bot. Now a game push (your_turn, game_over, nudge, match_found) carries
the game's own language (engine.Variant.Language) on push.Event, and the gateway
routes by it (falling back to service_language for non-game pushes). The New-Game
variant-gating guarantees the game's bot is one the player has started, so delivery is
never blocked.
Tests: proactiveNudgeGap unit + retimed TestRobotProactiveNudge; TestVariantLanguage;
emit your_turn/game_over language; TestNudgeRoutedByGameLanguage integration. Docs:
ARCHITECTURE (§7 nudge, §10/§13 routing), FUNCTIONAL (+ _ru), PLAN tracker.
The admin game detail now shows, per robot seat, the game's deterministic play-to-win
decision (from the bag seed) and — while it is that robot's turn — its scheduled next-move
ETA (sampled think-time delay, deferred past the sleep window), plus a caption with the
~40% global target. Wiring: robot.PlayToWin/NextMoveAt/PlayToWinTargetPercent exports,
account.IsRobot, game RobotSchedule (seed + turn-start). Tests: NextMoveAt invariants
(never early, never in the sleep window), PlayToWin export, and an admin render integration
test asserting the intent + ETA + target appear.
Ilia Denisov