dojo_cate/agents/plans/2026-09-25-dojo-board-and-sim.md

Il Labirinto del Dojo — board format, rules engine, simulator

Goal and scope

A small tabletop game (1–2 h, target 4 players, playable 3–8), gifted to a friend. Logic and balance first; graphics and cosmetics are out of scope for now.

Deliverables:

1. RULES.md — the rulebook (English while iterating; Italian final edition produced separately).
2. A text-based board format, with parser, full-board generator and validator.
3. A first playable board.
4. A rules engine + bots + Monte Carlo simulator to validate balance and pacing, and in particular to choose between rule variants A and B (B dropped, D28; now the Final Exam options, D29).

Decisions log

#	Decision	Why
D1	Kumite loser loses 1 belt (−3), never below 0	Developer requirement.
D2	"Punching up": belts change only on equal-belt fights or upsets	Prevents leader farming weak players; built-in catch-up.
D3	Kumite: 1d6 each, higher belt +1 per belt of gap, capped at +2	Uncapped d6 bonus made fights predetermined (gap 5 = 100%).
D4	Senshu rule: ties go to the attacker	WKF-inspired, one rule without exceptions, makes attacking slightly favourable so fights happen.
D5	Kumite triggers on crossing (entering an occupied square), always forced; winning attacker continues moving; chains allowed	Developer requirement; route choice gives the agency.
D6	Kumite loser is sent to own Start (corner Safe Room)	Developer requirement.
D7	Corner Safe Rooms: 3×3, 2 exits, no Kumite/effects/targeting, stacking allowed	Prevents spawn camping / spawn lock.
D8	Movement 2d6, exact count, orthogonal, no re-entering a square in the same move	Developer requirement + clarity.
D9	Most squares carry an effect from a small vocabulary (7 codes); ~30–40% Tatami	Developer requirement; limits reading load and analysis paralysis.
D10	Effects trigger only when stopping on a square	Avoids multiple triggers per move.
D11	Nebbia works like Monopoly Chance: the square stays active	Developer requirement.
D12	Progress track 0–17, 3 stripes per belt; squares ±1, Kumite ±3	Fine-grained board income without breaking pacing. Physical tracking method decided later.
D13	Nebbia deck is mostly movement/interaction/Tecniche, very few flat stripes	Prevents "stripe farming" that would make players avoid fights.
D14	Tecnica cards: hold max 1, played after dice, attacker first	Converts Nebbia luck into a reason to fight.
D15	Passo Falso returns to the start of the current move; skip-turn allowed only if rare (1 card)	Developer requirement.
D16	Tunnel: when stopping on it you may teleport; movement is over; occupied exit starts a Kumite	Developer confirmed.
D17	Meditazione: pass-through; ending on it forces one extra step	Developer rule.
D18	Central Dojo is one logical space, several entrances, Brown only, no exact count to enter	Avoids end-game "need exactly a 3" frustration.
D19	Final Exam: highest opponent defends; challenger wins → game; challenger loses → −3 and Start; defender gains nothing	Avoids the top-two flip-flop. Brown's extra stripes protect against the board, not the exam.
D20	Two rule variants to be decided by simulation: A (no Brown cap, higher-beats-lower 0) vs B (squares/cards cannot move 14→15, higher-beats-lower +1)	Neither is clearly better a priori. Superseded by D28.
D21	Board 16×16, 4×4 Dojo in the centre, authored as one 8×8 quadrant rotated 3× (C4 symmetry)	Fairness by construction. Small asymmetries may be wanted later (see Q2).
D22	Tooling in Python, environment managed with uv	Developer choice.
D23	Rules drafted in English; Italian final edition generated separately	Developer choice.
D24	Board format: see board/FORMAT.md. Tunnel pairing across quadrants via quadrant_offset in board/legend.toml (cell a in quadrant k ↔ cell b in quadrant k+o)	Every tunnel cell keeps exactly one partner under rotation.
D25	Only the Tunnel square is optional. Sfida (square and card), Irimi and Tunnel Segreto are mandatory; every Nebbia card must be resolved	Sfida prevents stalling; Nebbia cards are chances that can also turn out badly.
D26	Tecnica cards are secret: drawn face down, others only know whether you hold one, a replaced Tecnica is discarded face down, revealed only when played	Hidden information and bluffing. Bots must not see opponents' Tecnica identity (Phase 4).
D27	Edge rules (RULES.md v0.5, inline + FAQ): boxed-in → move as far as possible (safeguard; boards have no dead ends); Uke-saved attacker stops on its previous square, turn ends, no square effect; extra-step rule for ending on any unfightable pawn; tunnel exits with a meditating pawn unusable; meditating players cannot defend the Exam; Tecnica window after both dice, attacker first; relocations never fight or trigger squares; Tsugi-ashi has its own origin; becoming Brown mid-move opens the Dojo	Developer confirmed all ten.
D28	Variant B dropped (developer, after the Phase 5 baseline): no Brown cap; a higher belt beating a lower one gains nothing. Removed from engine, bots, simulator, RULES.md (v0.6)	B made games shorter (13 vs 18 rounds) instead of adding an endgame challenge; the cap barely bit and the +1 applied to every such win. Too complex for what it gave.
D29	Final Exam options under test: a ties go to the defender; c the defender fights as a Black belt (defender +1 vs a Brown challenger); d best of 3. Combinable (--exam ac). Option b (no belt bonus in the Exam) not pursued. Developer favours c	Baseline pass rate ~80%: the defender is usually 1–2 belts below the Brown challenger, who also gets Senshu.
D30	Simulator reporting: income per source as gains and losses separately (Kumite is zero-sum, so its net hid the flow); standings sampled at the end of every turn; ten one-sidedness measures (see 5.4)	Developer request after the Phase 5 baseline.
D31	Final Exam rule: the defender fights as a Black belt (option c; RULES.md v0.7). Options a (ties to the defender) and d (best of 3) stay as simulator switches only; --exam lists the options in force and defaults to c	c gave a 44% pass rate, more distinct challengers (1.58/game) and closer endings; d alone raised the pass rate to 91%.
D32	Phase 6 targets confirmed by the developer as a starting point (table in Phase 6)	Q5.
D33	Fatica fix: test option 2 first — a chance square (stop on it, roll 1d6: 1–2 lose a stripe, 3–6 gain one) replacing Fatica and some Allenamento; then option 1 must also be tested — Fatica costs a stripe when walked through as well as when stopped on (breaks D10 for that square only). Options 3 (fewer paths: board rework) and 4 (fewer / once-per-room Allenamento) kept in reserve. The casual bot (6.0.1) is built regardless	Q6. Any on-stop penalty is avoidable when a move reaches ~24 end squares; the chance outcome cannot be dodged. Developer likes 1 and 2.

Phases

Phase 0 — Rules consolidation

• 0.1 Write RULES.md v0.4 with variants A/B marked.
• 0.2 RULES.md v0.5: mandatory effects, Tecnica secrecy, edge rules and FAQ (D25–D27).

Phase 1 — Project scaffold and board format

• 1.1 uv init project (package dojo), Python version pinned via uv; dev deps: pytest, ruff. No runtime deps (legend in TOML, parsed with stdlib tomllib).
• 1.2 board/FORMAT.md — the format specification:
  • ASCII grid: + corners, | vertical walls, --- horizontal walls, 3-char cells with a centred code.
  • Cell codes: S safe room, D dojo, . A F ? P K (Allenamento/Fatica were +/-, changed so no code looks like a wall), digits = tunnel pair ids.
  • Outer border must be fully walled.
  • Dojo entrance = open edge between a D cell and a non-D cell.
  • Cross-quadrant tunnel links declared in board/legend.toml.
• 1.3 Parser: quadrant.txt → cell grid + wall set.
• 1.4 Generator: rotate the quadrant 90°/180°/270° around the board centre → full 16×16 model; write board/board.txt (generated, never hand-edited).
• 1.5 Graph model: cells as nodes, open edges as links. The Dojo is handled as one cell set (impassable, entrances = open D/non-D edges); treating it as a single space for movement lands in the rules engine (3.3).
• 1.6 Validator:
  • every non-Dojo square reachable from every Safe Room;
  • each Safe Room has exactly 2 exits, on different sides;
  • no Safe Room lies on a shortest path between two other points (not a shortcut);
  • every tunnel id has exactly one partner;
  • Dojo has ≥1 entrance per quadrant;
  • report: square-type mix and Tatami %, shortest distance from each start to the Dojo.
• 1.7 CLI: uv run dojo board validate, uv run dojo board render.
• 1.8 Unit tests for parser, rotation, validator.

Phase 2 — First board

• 2.1 Draft the first quadrant (board/quadrant.txt), following D7, D9, D18.
• 2.2 Validate and iterate until clean.
• 2.3 Developer review of the layout (approved as draft 1).

Phase 3 — Rules engine

• 3.1 Game state: pawns, track positions, hands, deck/discard, meditation status, turn order.
• 3.2 Rule configuration object: variant A/B, Kiai value, stripes per belt, starting position, player count.
• 3.3 Movement enumeration: all legal exact-length self-avoiding walks, with Kumite on crossing, chain continuation, Dojo entry with ≥1 step left, Meditazione extra step.
• 3.4 Kumite resolution: gap bonus cap, Senshu, Tecnica timing, consequences table per variant, Uke placement.
• 3.5 Square effects and Nebbia cards (all 13 card types).
• 3.6 Final Exam.
• 3.7 Unit tests covering every edge rule in RULES.md (tests/test_engine.py, tests/test_movement.py; mutation-checked: breaking Senshu, bonus cap, chain continuation, Meditazione step, variant B cap, Safe Room or meditator immunity each fails tests).
• Code: src/dojo/rules.py (config, variants, deck), movement.py (walks), engine.py (Game, Agent protocol, Randomness), events.py (event log for metrics).

Phase 4 — Bots

• 4.0 Hidden information: agents receive a GameView snapshot (Game.view(player)), never the Game: opponents' Tecnica shows only as holds_tecnica; the event log (which records CardDrawn) is not visible to agents (D26).
• 4.1 Random bot (baseline): RandomAgent(rng) in src/dojo/bots.py.
• 4.2 Heuristic bot: HeuristicAgent(profile). Value = track position; once Brown, plus DOJO_PULL (0.3) per step closer to the Dojo. Scores each offered path as the expected value change over the chain of Kumite (exact 1d6-vs-1d6 odds with belt bonus and Senshu, ±0.1 per Tecnica held), then the stop square's effect (Nebbia worth 0.2, Sfida = best target, Tunnel = better of staying/exit). Exam = 100 × pass chance. Tecnica played only when losing (Kiai only if it turns the fight). Known simplifications: Meditazione extra step, Passo Falso origin after a chain, opponents' replies.
• 4.3 Profiles (PROFILES): losses weighted by risk, opponents' value changes by rivalry, Tecnica keep order. balanced (1.0, 0.5, Kiai>Kaeshi>Uke), farmer (2.5, 0.2, Uke first), aggressive (0.5, 1.0).
• Smoke run (60 seeds, real board, 1 heuristic vs 3 random): heuristic wins 58–60/60 for every profile and both variants; ~20–22 rounds; ~1,300–1,450 turns/s. Four heuristic bots: ~18.7 rounds. Finding to check in Phase 5/6: attacking a higher belt risks nothing for a non-Brown player (losing costs 0 stripes; Start is no worse than elsewhere), so every profile attacks upward.

Phase 5 — Simulator and metrics

• 5.1 Monte Carlo runner over a config matrix; seeded and reproducible. src/dojo/sim.py: Scenario (variant × players × Kiai bonus × start position × lineup), matrix, run(files, scenarios, games, seed, jobs). Game i uses seed base + i in every scenario (same dice across scenarios); the lineup rotates one seat per game; process pool, results independent of jobs.

• 5.2 Metrics (src/dojo/metrics.py, computed from the event log; Kumite counts exclude the Exam):

  • game length in rounds and estimated minutes (45 s per turn + 30 s per Kumite);
  • Kumite per round, upset rate, higher-beats-lower rate, longest chain per game (Kumite attacked by the active player in one turn);
  • win rate by seat and by bot profile (per seat occupied);
  • exam attempts per game, exam success rate;
  • turns started on 14, longest streak (variant B deadlock check);
  • net stripe income per turn: squares vs cards vs Kumite vs Exam; square income in the player's own quadrant vs elsewhere (home farming);
  • lead changes per game (strict leader), final spread.

• 5.3 Report output: uv run dojo sim prints a text summary per scenario; --csv writes one row per game (src/dojo/report.py). Commands in README.md.

• Baseline (1,000 games per variant, 4 players, lineup balanced/farmer/aggressive, seed 0), for Phase 6:

  Metric	A	B
  Rounds mean (p10–p90)	18.4 (14–23)	13.1 (9–17)
  Minutes mean (p10–p90)	66 (50–85)	46 (33–62)
  Kumite per round	1.25	1.16
  Upsets / higher beats lower	29% / 55%	27% / 52%
  Exam attempts per game, pass rate	1.26, 79%	1.22, 82%
  Turns on 14 per game, longest streak	1.26, 4	1.73, 7
  Income per turn: square (home / away), card, Kumite	+0.52 (0.38 / 0.14), 0.00, +0.04	+0.54 (0.39 / 0.14), 0.00, +0.22
  Lead changes, final spread	5.6, 9.3	3.5, 11.5
  Wins by seat	23–27%	23–27%

• 5.4 Follow-up to the baseline review (D28–D30):

  • remove variant B; --variant replaced by --exam (Exam options, RulesConfig.exam_ties_to_defender / exam_defender_black / exam_rounds); "turns on 14" metric removed with it;
  • income per source as gains / losses;
  • one-sidedness measures, sampled at turn ends: (1) gap 1st–2nd (mean per game) and winner margin over the best rival at the end; (2) share of turns the winner led; (3) halfway leader wins; (4) point of the game of the last lead change; (5) rivals within one belt of the winner at the end; (6) share of player-turns more than two belts behind the leader, and the worst player's share; (7) rank swaps between any two players; (8) Kumite lost by the leader; (9) distinct Exam challengers; (10) winner's own turns to reach Brown.

• After 5.4 (300 games per option, 4 players, lineup balanced/farmer/aggressive, seed 0):

  Metric	none	a	c	d
  Rounds mean (p10–p90)	18.5 (14–23)	19.3 (14–25)	21.9 (16–29)	18.0 (14–22)
  Minutes mean	67	70	80	66
  Exam pass rate, attempts per game	81%, 1.24	67%, 1.50	44%, 2.28	91%, 1.10
  Distinct challengers per game	1.13	1.24	1.58	1.06
  Winner margin at the end	4.7	4.6	3.9	4.8
  Halfway leader wins	40%	41%	40%	41%
  Rivals within one belt at the end	0.32	0.37	0.62	0.30
  Player-turns out of contention	22%	22%	21%	22%

  Also measured: Kumite moves +0.44 / −0.40 stripes per turn; heuristic bots almost never stop on Fatica (square losses 0.0002 per turn vs 0.08 for random bots): with 2d6 and many paths an Allenamento is nearly always reachable. Seat 3 (last in turn order) won 28–31% in every option.

Phase 6 — Balance experiments

Method (applies to every step):

• Runs use uv run dojo sim. Default 1,000 games per scenario (a 25% win rate is then known to about ±1.4 pp); 4,000 games where seat effects are measured (about ±0.7 pp).
• Compared scenarios share seeds (--seed 0), so differences come from the rules, not the dice.
• Every conclusion is checked on at least two lineups (mixed balanced,farmer,aggressive, and one same-style lineup), because results depend on bot quality.
• One change at a time. When a change is adopted, re-run the 6.1 baseline so later steps start from the current rules, and log the decision (D-number) here and in RULES.md.
• Results go in this file as a table per step (command line, scenario, key measures).

Next action: 6.0 (tooling), then 6.1. Everything up to D33 and RULES.md v0.7 is committed; commit only when the developer asks.

Targets (confirmed by the developer as a starting point, D32):

Measure	Target
Minutes, 4 players	mean 60–90, p90 ≤ 110
Exam pass rate	35–55%
Halfway leader wins (4 players)	35–55%
Player-turns out of contention	≤ 20%; worst player mean ≤ 35%
Rivals within one belt of the winner at the end	≥ 0.5
Win rate by seat, 4 players	each 25% ± 3 pp
Win rate by bot style (mixed lineup)	spread ≤ 6 pp
Games finished within 200 rounds	100%, every lineup

Steps:

• 6.0 Tooling needed by the experiments
  • 6.0.1 "Casual" bot: the heuristic bot scoring only a small random sample of the offered moves (sample size is a parameter, default 6), as a stand-in for a human who cannot compare ~24 end squares every move. Added to BOTS as casual.
  • 6.0.2 --summary-csv PATH: one row per scenario with the summary measures, to compare scenarios side by side.
  • 6.0.3 Seat breakdown in the summary: per seat, mean final track, Exam attempts, and share of games where that seat defended the Exam (for 6.2).
  • 6.0.4 Square reachability measure: share of moves where an Allenamento / Fatica end square is reachable, and mean distinct end squares per move (the Phase 6 probe, made a metric; for 6.4).
• 6.1 Baseline on rules v0.7 (Exam c): 4 players, 1,000 games, lineups mixed / balanced / casual / random. Record the table; check it against the targets.
• 6.2 Seat order (monitor; developer concerned): 4,000 games, 4 players, lineups mixed and random; 2,000 games at 3 and 6 players. If a seat is outside 25% ± 3 pp, diagnose with the 6.0.3 breakdown (hypotheses: moving last means seeing everyone else move first; Exam defender selection; Sensei / Peso cards) and bring candidate fixes to the developer. No fix without agreement.
• 6.3 Style dynamics: same-style lineups (farmer, aggressive, balanced, casual) and one-against-three (aggressive,farmer,farmer,farmer, farmer,aggressive,aggressive,aggressive, balanced,farmer,farmer,farmer). Watch: all-farmer stalling (length, games finished, Kumite per round), a dominant style, time out of contention.
• 6.4 Fatica and the square economy (D33). Each candidate is a board draft in board/drafts/ (new square codes need Square, board/FORMAT.md, validator stats and RULES.md entries) and/or a RulesConfig switch, compared with the 6.1 baseline on square gains / losses per turn, reachability (6.0.4), game length, style win rates, casual vs heuristic gap:
  • 6.4.1 Option 2, chance square: new code (proposal C, name to choose with the developer, e.g. "Sorte" / "Randori") — on stop roll 1d6, 1–2 → −1 stripe, 3–6 → +1. Draft: replace every Fatica and some Allenamento with it (start: all F plus about a third of A, keep the square mix inside the validator's Tatami range). Bot: value = expected change (+1/3 stripe, risk-weighted: gain 2/3, loss 1/3). Try variations of the split (e.g. 1–3 / 4–6) if income is off.
  • 6.4.2 Option 1, Fatica on crossing: RulesConfig.fatica_on_crossing — each Fatica square entered during a move costs 1 stripe, 1 in total per square whether or not the move stops there (developer, D33); stopping on it adds nothing more. Engine: apply in _walk per square entered (not on teleports / relocations, which never walk). Bot: count Fatica crossed in _path_score. Likely needs fewer Fatica squares; test on the current board and on a draft with fewer F.
  • 6.4.3 Compare 6.4.1, 6.4.2 and both together; bring the table to the developer for a decision (then RULES.md and D-number).
• 6.5 Home farming: after 6.4, if the own-quadrant share of square income is still above 60% (baseline: 71%), move Allenamento squares away from the Safe Rooms in a board draft (dojo sim --quadrant board/drafts/...) and compare. The board must still pass dojo board validate.
• 6.6 Kiai +2 vs +1: 1,000 games each on two lineups. Watch the Exam pass rate, upset rate and how often a Tecnica turns a fight.
• 6.7 Player counts: 3 / 4 / 6 / 8 players, start 0; plus start 3 at 6 and 8 players. Minutes per count; decide whether 6+ players start on Yellow.
• 6.8 Consolidation: the final configuration at 3 / 4 / 6 / 8 players with all lineups, 2,000 games each; every target checked; RULES.md v0.8 with the decisions; open items moved to Phase 7.

Phase 7 — Finalisation (later)

• 7.1 Freeze rules.
• 7.2 Italian edition.
• 7.3 Physical tracking method and components; printable board.
  • Tunnel pairs need unique labels on the printed board (the text format repeats each digit in all 4 quadrants).

Questions

Resolved

• Tie rule → Senshu (attacker wins).
• Several opponents on one square → impossible (loser is teleported); only exception handled by the Meditazione extra-step rule.
• Exam loss → −3 and Start; defender gains nothing.
• Tunnel → teleport optional on stop, movement over.
• Optional vs mandatory effects → D25.
• Engine edge rules → D27.
• Sfida squares → keep, balance via low count.
• Il Peso della Cintura → keep (1 card).
• Player count → focus 4, support 3–8.
• Tests → the agent runs the suite (uv run pytest), plus ruff check, ruff format --check, pyright.
• Minutes estimate → 45 s per turn, +30 s per Kumite.
• Q4 Target net income per turn → current pace is fine: A already runs ~66 min (p90 ~85); the winner's pace is measured instead of a table average.
• Variant A vs B → B dropped (D28).
• Final Exam → the defender fights as a Black belt (D31).
• Q5 Phase 6 targets → confirmed as a starting point (D32).
• Q6 Fatica avoidable (bots stop on it once in ~4,000 turns; ~24 distinct end squares per move; Allenamento reachable on 79% of moves, Fatica never forced) → test the chance square first, then Fatica on crossing (D33).
• Safe Room placement → the owner places the pawn on any square of their room (setup and when sent to Start).

Open

• Q7 Casual bot sample size: 6 offered moves is a guess at human play; revisit if 6.1 shows it is far weaker or stronger than the heuristic bot.
• Q2 Board asymmetry: keep the quadrant as source of truth, or later switch to the full board as source of truth with a symmetry report (warnings) instead of generation? (Deferred by the developer.)

Risks

• Movement enumeration: self-avoiding walks of length up to 12 can explode in open rooms. Keep rooms small; prune by outcome (destination + ordered opponents crossed + Dojo entry).
• Engine speed ~1,400 turns/s (random and heuristic bots, real board). If Phase 5 needs more: precompute neighbour lists in Board.
• Simulation conclusions depend on bot quality; compare several profiles before trusting a result.
• Board draft 1 puts 4 Allenamento in each 3x3 room next to the Safe Room: possible "home farming" (see the Phase 2 review). Measured (Phase 5 baseline): square income is +0.38/turn in the own quadrant vs +0.14/turn elsewhere; 6.5 decides whether that is a problem.

External documentation

• uv — https://docs.astral.sh/uv/ — project init, dependency and Python version management.
• Python tomllib — https://docs.python.org/3/library/tomllib.html — stdlib TOML parser for legend.toml.
• pytest — https://docs.pytest.org/ — unit tests.
• Ruff — https://docs.astral.sh/ruff/ — lint and format.
• WKF Kumite competition rules (wkf.net, "Rules") — source of the Senshu concept.