rules.md

Cogmud rules

Six cogs, one town, fourteen turns. Every action is ONE SENTENCE of plain English; there is no menu of moves anywhere.

The nine rooms

Exits are symmetric and complete: a ring 1-2-3-4-5-6-7-8-1 plus spokes from Market Square to 1, 3, 5 and 7. Every room is within 2 moves of Market Square and the graph diameter is 4. dark rooms are the only rooms where robbery can succeed.

The six goods

base value is the fixed reference valuation SCORING uses. It never moves with the market, so a seat's score never depends on which shop it happens to be standing next to.

The five shopkeepers

Each stands in one room forever, deals only in the goods on its list, and starts with 120 coin.

Prices move with stock

Integer arithmetic only, per shopkeeper per good:

ask(n, k) = clamp(base[k] + 1 * (6 - stock(n, k)), max(2, base[k] div 2), base[k] * 3)
bid(n, k) = max(1, ask(n, k) * 2 div 3)

At stock 6 a good sells for exactly its base value; at stock 0 it costs base + 6 (capped at three times base); at stock 12 it costs base - 6 (floored at half base, minimum 2). The bid is two thirds of the ask: the spread is the shopkeeper's living. Each unit of a multi-unit purchase is priced from the stock at the moment THAT unit changes hands - buying two hides from a shop holding 8 costs ask@8 + ask@7 = 4 + 5 = 9. That is the whole supply curve, and it is why cornering a shop's stock is a real strategy. At each turn's open after the first, every shopkeeper adds +1 to exactly one good on its list - index turn mod list length - up to a cap of 12. Supply is slow, finite and predictable.

Commissions

Guildmaster Vell at the Guildhall posts and settles EVERY commission in the game. Each seat holds exactly two, private to it, drawn from the seed from {hide, nails, rope, salt} (never lamp or relic - those are pure trade goods), each for 2 units. Handing goods to a shopkeeper is how a commission is filled: give Vell a good one of your open commissions names and each unit banks 4 points, with a further 8 when the commission is finished. PART OF A COMMISSION COUNTS. Goods handed to any other shopkeeper, or to Vell without a matching open commission, enter its stock and score nothing - the goods are gone.

The turn

An episode is turns turns (default 14). Decisions inside a turn are SIMULTANEOUS: all six sentences go out in one parallel batch and nothing a seat writes in turn t is visible to any other seat before turn t + 1.

Initiative is a deterministic rotation with no randomness: on turn t the seats resolve in the order (k + t) mod 6 for k = 0..5. Every seat stands at the front of the queue exactly turns / 6 times. Where two seats contend for the same stock, the same item on the floor, the same offer or the same victim, THE EARLIER INITIATIVE WINS and the loser's action resolves against what is left, or fails with a named reason.

For each turn, in this exact order:

1. Open. Offers posted two or more turns ago expire (an offer lives exactly one turn: posted on t, acceptable only on t + 1). Every retainer's counter ticks down; at zero the bond clears. Every shopkeeper restocks one good - at the open of every turn after the first, since the opening stock in the table above is what the shops hold on turn 1. Last turn's public acts become what each seat reads as what happened here.
2. Deadline check, before the batch and never mid-turn.
3. Rate floor: at least 12 seconds between LLM batches, skipped entirely when there are no credentials.
4. Collect: one parallel batch of six.
5. Parse: every sentence through the same pure grammar.
6. Resolve, in this class order, each class in initiative order, each sub-step appending its own event as it resolves:
   1. Speech - every say field and every spoken line is posted to the speaker's START-OF-TURN room.
   2. Shops - buy, sell, hand over, ask.
   3. Ground - take, drop.
   4. Cog to cog - give, offer a trade, offer a hire, accept.
   5. Robbery - against START-OF-TURN positions. You cannot dodge an ambush by walking away.
   6. Movement.
7. Book-keeping. Wealth and score are derived from state, never accumulated.

The thirteen intents

A sentence the grammar cannot read is a legal no-op with a reason naming what was missing, and the seat is told the reason in its next observation. That is how a policy learns the grammar, and it is why no menu is needed.

Robbery, deterministically

Let retainersPresent(x) be the number of seats hired to x, still bound, and standing in the robbery's room at the turn's start.

A = 1 + retainersPresent(robber) + (1 if the room is dark else 0)
D = 1 + retainersPresent(victim) + (0 if the room is dark else 2)   # the watch
robbery succeeds iff A > D

• Lit room, no hirelings: A = 1, D = 3 - the watch always stops you. Robbery is possible ONLY in The Docks and Cutpurse Alley.
• Dark room, no hirelings: A = 2, D = 1 - it succeeds.
• Dark room, the victim has one hireling beside it: A = 2, D = 2 - it fails. A bodyguard is worth exactly one mugging.
• Dark room, both sides have one hireling: A = 3, D = 2 - it succeeds. Bringing muscle beats hiring muscle, so protection is a market, not a shield.

On success the robber takes ONE item - the victim's highest-base-value good, ties broken by lowest id - or, if the victim carries nothing (or the robber has no free slot), min(victim's coin, 10) coin; with neither, nothing_to_take. On failure the robber pays min(its coin, 8) to the victim. Either way the attempt is public in the room. A retainer can never rob its own employer.

What a seat sees, and what it never sees

A seat sees the turn number, its alias, its purse and pack with each good's reference value and its free slots, its commission book with points banked and outstanding, the room it stands in (name, description, exits BY DESTINATION NAME, the goods on the floor, the aliases of every other cog present, and the shopkeeper here with its full trade list: good, stock, ask, bid and its remaining coin), every public act and spoken line here last turn (at most 12 lines of at most 200 runes), the offers open to it, its retainer standing, the town map (every room's name, its exits and which keeper shops there - but NOT those keepers' stock or prices), the verbatim outcome of its own last sentence, its private notes, and a twelve-line phrasebook of example sentences.

A seat NEVER sees any other seat's coin, pack, commissions, notes or score; anything at all happening in another room; the stock or prices of a shopkeeper it is not standing next to; the seed; or another seat's raw sentence except through the public act lines of its own room.

Every cog knows the map and nobody knows the town. Every NOUN a sentence could need is spelled out in the observation, so a model never has to guess a name - and nothing tells it what it is allowed to DO.

The two endings

• complete - all turns resolved. The expected value.
• deadline - the play deadline (60% of the episode timeout) was reached between turns, so the episode settled early. Scores come from the state as it stands; because score is derived from wealth and deliveries rather than averaged per turn, a short honest episode is on the same scale as a full one.

There is no other value. There is no bankruptcy (coin can never go negative), no elimination and no walkout: a seat that never connects plays with an empty operator prompt, and a seat whose decision fails plays the scripted baseline.