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Game Theory Tagging

From the Meridians Wiki · Public · Maintained · joint

Every scene is additively decomposed into a sequence of 2×2-style strategic games, one per strategic beat (written to scene.gameAnalysis, never mutating deltas). Each game names the shape of a decision — the full space of choices each party could have made and the consequence of every pairing — and marks the realized cell (what the author actually wrote). The shape says how stake can move; the realized cell says how it did move; the gap is what was left on the table.

Tagging happens on three layers: each game carries a game kind, an action axis, and a game type (shape); the realized outcomes feed ELO / stake metrics; and those metrics aggregate into per-player behavioural tags.

Game Kind

KindShapeDescription
duelN×M matrixTwo strategic agents, each with a menu of actions. Every (A-action, B-action) pairing is a scored cell. Default kind.
solorow of optionsOne decider facing a pivotal choice against the world (reality in the other seat). A menu of options, one immediate outcome each — no opponent column.

Action Axes (the dimension the choice trades on)

Both players' actions live on the same axis — the thing that shifts as a result of the decision, not the surface topic. Eleven axes (consolidated from earlier finer sets; e.g. control and confrontation fold into pressure, moral into commitment):

AxisQuestion it asks
informationreveal ↔ conceal — what facts about the world does each side expose or hide?
identityclaim ↔ disown — do I assert who I am, or distance myself from it?
trustextend ↔ guard — do I lower my defenses, or keep them up?
allianceally ↔ separate — are we on the same side going forward, or not?
statusassert ↔ defer — do I push for the higher position, or yield rank?
pressurepress ↔ yield — how much force am I applying, or absorbing? (absorbs control, confrontation)
stakesescalate ↔ deescalate — am I raising or lowering what's on the line?
resourcestake ↔ give — who ends up holding the resources / lives / knowledge?
obligationincur ↔ discharge — am I taking on a debt/favor, or paying it off?
commitmentcommit ↔ withdraw / hedge — am I binding myself, or keeping options open? (absorbs moral)
timingact ↔ wait — do I move now, or hold and watch?

Game Types (the strategic shape)

Sixteen shapes (consolidated from 19 — battle-of-sexes folds into coordination, cheap-talk into signaling, pure-opposition drops, anti-coordination renamed divergence). Classified by a decision procedure over scope → mechanism → information × preference.

GroupTypeShape
Symmetric-infocoordinationBoth want to end up in the same place; stake moves together when actions match (incl. battle-of-sexes flavour).
stag-huntCoordination with a trust gate — big shared prize vs. the safe solo play. Payoff-dominant Nash is risk-dominated.
dilemmaMutual cooperation pareto-dominates Nash, but each has a private incentive to defect (prisoner's-dilemma).
chickenBoth want the other to yield; if neither does, both crash (incl. war-of-attrition).
divergenceBoth actively want to differ on a shared axis. (One-sided → stealth or zero-sum.)
zero-sumGrid literally sums to zero in every cell — any +X for one is −X for the other.
Asymmetric-infosignalingInformed party reveals type via a costly, hard-to-fake action (absorbs cheap-talk when costly enough).
screeningUninformed party designs a mechanism to sort agents by type — tests, auditions, loyalty trials.
principal-agentDelegation and hidden action — task handed off and execution opaque (both required).
stealthCovert action vs. an unaware observer whose only move is attention allocation (no delegation).
MechanismstackelbergSequential commit-then-respond — leader moves visibly first, follower best-responds.
bargainingOffer → counter → accept/reject rounds (one-shot ultimatum is the degenerate case).
commitment-gameWhether one party can credibly self-bind IS the game (vow, burned bridge, hostage, contract).
Multi-partycontestN-player rank-ordered competition for a prize.
collective-actionN-player threshold contribution with free-rider dynamics.
DegeneratetrivialNo real strategic content — the choice is in name only. Used sparingly.

Stake & ELO Metrics

Each outcome cell carries integer stake deltas in [-4, +4] per player — how much that outcome advances or harms a player's arc-level interests if it were the one that happened. Magnitude is inflection, not drama, and is calibrated against the whole work, not the sentence:

ValueMeaning
±4Arc-defining / irreversible — the trajectory itself changes. Rare.
±3Major — clearly shifts the balance; hard to undo.
±2Moderate — a real but recoverable move (the modal score).
±1Minor — a nudge; a small edge or cost.
0Neutral — nothing material moved.

Over-crediting is the common failure: most decisions are ±1–±2, and a beat where everything scores ±3/±4 is inflated. The two kinds of decision read the scale differently: a two-player decision is scored on relative reward — each side's delta and the differential ΔA − ΔB (who gains relative to whom). A one-player decision is scored on its field of alternatives — each option's outcome, so the chosen option's reward is weighed fairly by its contribution against what else was available (taking +2 when +4 was on the table is a costly call), not in isolation.

MetricDefinition
Margin scoreclamp(0.5 + (ΔA − ΔB)/16, 0, 1) — continuous score ELO consumes; folds margin-of-victory into the math (+4/−4 crush = 1.0, +1/0 edge ≈ 0.56, tie = 0.5). Solo: clamp(0.5 + ΔA/8, 0, 1) against par.
Game score (W/L/D)Binary 1 / 0 / 0.5 for display — not what ELO reads.
ELOELO_INITIAL = 1500, ELO_K = 32; K_effective = K × min(1, max|stake|/4) so crucial moments move ratings far more. Solo decisions play reality at par (1500), and only the decider's rating moves.
NashA realized cell is a (weak) pure-strategy equilibrium if neither player could unilaterally improve their stake delta. Descriptive, not normative — off-Nash cells are exactly what ELO learns from.
Stake rankRank of the realized cell among all outcomes by stake delta for a player (1 = best available).
Arc costStake left on the table — max(stake in realized row/column) − realized stake. Rises when a player trades local stake for identity / principle / arc.

Behavioural Tags

ELO trajectory, outcome shape, game-type participation, and role split aggregate per player into orthogonal tags. One domain-role headline leads; mechanical tags follow.

Domain role (headline, one max) — a cross-genre pattern over the signals:

TagPattern
prime moverRising ELO, leads the play, repeatedly lands above what the grid predicts — the world bends around them.
adversaryDominates grids at others' expense; lives in conflict / power-framing games.
tragic figureAbsorbs losses for others and pays for it — ELO declines while carrying the sacrifice.
mentorCooperative, steady ELO, gives more stake than they take.
comebackArc shifts upward — later outcomes better than early; growth / redemption.
slippingArc shifts downward — started stronger than they end.
tricksterInfo-asymmetric games, high variance, mostly ends ahead.
counterforceAlmost always responding, almost always in conflict, ELO near baseline.
anchorHigh participation, near-baseline ELO, broadly cooperative — the stable presence.

Outcome shape (one max): extractor (wins at another's expense) · sacrificial (pays so others gain) · scorched-earth (both-lose cells dominate) · uneven ally (cooperates but stacked in their favour) · ally (genuine even cooperator).

Trajectory (one max): dominant (lands near the top of every grid) · rising / falling (ELO climbed / eroded ≥80) · high-variance (large rating changes) · steady (rating barely moves).

Solo decision style: soloist (mostly 1-player bets against the world) · sure-handed (usually takes the stake-maximising option) · gambler (routinely passes up the safe-best for the upside).

Solo decision axis: solo: X — the characteristic dimension of a player's bets against the world, isolated from their duel axis affinity. In a solo decision reality sits in the other seat, so this names the silent counterpart they keep playing. On the timing axis that counterpart is literal — the clock — so solo: timing marks a player forever choosing when to move (act ↔ wait) against time itself.

Strategic style (one max): defies the odds (wins off-Nash cells rational play says they shouldn't — protagonist signature) · strategist (lands on Nash, plays the defensible move) · off-script (rarely plays the rational move).

Strategic agency (from game-type participation): schemer (plays the information game and wins it) · power-broker (sets the terms, first mover in commitment / bargaining) · combatant (lives in zero-sum / chicken / divergence) · coordinator (builds shared action in alignment games).

Arc shift: upward arc / downward arc (late-vs-early stake split).

Relational: rival: X (losing record concentrated against X) · leads: X (winning record concentrated against X).

Role bias: initiator (almost always Player A) · responder (almost always Player B).

Affinity: axis: X (most choices trade on axis X) · X-heavy (most decisions sit inside game-type X).

Files: src/lib/core/game-theory/game-theory.ts (pure math), src/lib/engine/ai/game/game-analysis.ts + src/lib/engine/prompts/scenes/game-theory.ts (LLM decomposition), src/types/domain/game-theory.ts (ActionAxis, GameType, label tables), src/shell/topbar/modals/GameTheoryDashboard.tsx (behavioural tags), src/shell/stage/views/mind/DecisionView.tsx (per-scene payoff matrix — the Decision Matrix).