FAILURE MAP
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FA-83531 / Card game rule engines / Open access

Court cards count their rank number toward fifteen · case 01

J-5, Q-5 and K-5 no longer make fifteen.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Card value is the rank index without the ten cap.

VERIFIED REPAIR

Cap every card at 10 for fifteens.

Unsuccessful approach: Capping court cards but counting the ace as 11 breaks fifteens with aces.

Case contract

Input [four_card_hand, starter, is_crib]. Fifteens (any 2-5 cards, A=1, T/J/Q/K=10) score 2; each pair 2; runs score their length for every distinct combination of the longest run length; a four-card hand flush scores 4 (+1 with the starter) but the crib scores only a five-card flush; a hand jack matching the starter suit scores 1. Return the total.

Why this case matters

Card-game engines, scoring apps and online tables apply this rule automatically on every hand.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return order.index(c[0]) + 1
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += runs * size
            break
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['7C', '7S', '8S', '9H'], 'JD', True], 12], [[['AH', 'KC', 'TH', '4S'], '6D', True], 4]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5], [[['JC', 'KH', '4D', '6S'], 'AH', True], 4]], [[[['9S', '3S', 'QS', 'TS'], 'QH', False], 6], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['7C', '8C', '9D', 'AD'], '6S', False], 10]], [[[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['JS', '8S', '2S', 'TS'], '2D', False], 6], [[['5H', '2H', 'QH', '6H'], '7S', True], 7]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 066Passed
hand score case 104Failed
hand score case 21212Passed
hand score case 344Passed
hand score case 466Passed
hand score case 559Failed
hand score case 61212Passed
hand score case 755Passed

SHA-256 / f8bfeaed06d3609cd2662e9650fcbee7b7ba09a287ea933716cc85197af6ddc1

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return min(order.index(c[0]) + 1, 10) if c[0] != 'A' else 11
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += runs * size
            break
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['7C', '7S', '8S', '9H'], 'JD', True], 12], [[['AH', 'KC', 'TH', '4S'], '6D', True], 4]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5], [[['JC', 'KH', '4D', '6S'], 'AH', True], 4]], [[[['9S', '3S', 'QS', 'TS'], 'QH', False], 6], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['7C', '8C', '9D', 'AD'], '6S', False], 10]], [[[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['JS', '8S', '2S', 'TS'], '2D', False], 6], [[['5H', '2H', 'QH', '6H'], '7S', True], 7]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 046Failed
hand score case 124Failed
hand score case 21212Passed
hand score case 324Failed
hand score case 466Passed
hand score case 599Passed
hand score case 61012Failed
hand score case 735Failed

SHA-256 / 0aa58a9cfdaa63a2006e4f663c3058903230f698da444c8bcb652c879465e44d

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return min(order.index(c[0]) + 1, 10)
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += runs * size
            break
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['7C', '7S', '8S', '9H'], 'JD', True], 12], [[['AH', 'KC', 'TH', '4S'], '6D', True], 4]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['AD', 'JS', '2H', 'QH'], '4S', False], 5], [[['JC', 'KH', '4D', '6S'], 'AH', True], 4]], [[[['9S', '3S', 'QS', 'TS'], 'QH', False], 6], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['7C', '8C', '9D', 'AD'], '6S', False], 10]], [[[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['JS', '8S', '2S', 'TS'], '2D', False], 6], [[['5H', '2H', 'QH', '6H'], '7S', True], 7]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 066Passed
hand score case 144Passed
hand score case 21212Passed
hand score case 344Passed
hand score case 466Passed
hand score case 599Passed
hand score case 61212Passed
hand score case 755Passed

SHA-256 / 2c990a29e00ab28f4e9cb2bca98be21fe657bda4215e58e8b2fa3b235e2c6fac

Verification & scope

A bounded toy rule contract stated explicitly in the contract field; cards are two-character codes (rank, suit). Not a complete implementation of any published rulebook or casino table rules. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:50:22.548556+00:00.

Case digest / cb2a08906fb814318e961cfc0836cdf33724804862b9d9ef7fb6cab49b1625f4