Sumi Steps

Goal

Rake ink through nine Zen gardens. Each garden is a small rectangular grid of sand plots: starting on Stone 1, draw one unbroken ink stroke that visits every plot exactly once, passes the numbered stones in strict order (1, then 2, then 3, ...), and comes to rest on the final stone. Completing a garden immediately banks its points and starts the next; completing all nine ends the run (there is no fail state and no timer). endRun stops the run early, keeping every point banked so far.

Scoring

Higher is better (descending), maximum 3156. Reaching a stone for the first time in a garden: +10 (latched, never re-awarded, never lost). Completing garden L: +75 + 25 × L (garden 1 = 100 ... garden 9 = 300) plus a Clean Brush Bonus of max(0, 2 × cells − 2 × wasted), where wasted = undos ×1 + resets ×10 for that garden. Finishing the whole run with zero wasted steps adds the Still Water bonus (+250), which endRun never pays. Score is strictly monotonic: undo, reset, endRun, and invalid moves never reduce it — waste only shrinks future bonuses.

Rules

A step moves the stroke head one plot up, down, left, or right. A step is valid only if the target is in bounds, no bamboo fence blocks the shared edge, the target is not already inked (except the plot just behind the head, which lifts the ink exactly like undo), and, if the target holds Stone k, stones 1..k-1 are already inked. Once the head rests on the final stone, only backtracking or undo leaves it. Invalid actions are free no-ops with a teaching error, never a penalty. undo lifts the head plot (+1 wasted step); reset sweeps the current garden back to Stone 1 (+10 wasted steps); neither ever touches completed gardens or banked score. A garden completes automatically the instant every plot is inked and the head rests on the final stone. Every garden is generated solvable; the same seed always produces the same nine gardens, and the solution is never revealed.

Action grammar

{
  "oneOf": [
    {
      "type": "object",
      "properties": {
        "type": {
          "const": "step"
        },
        "direction": {
          "enum": [
            "up",
            "down",
            "left",
            "right"
          ],
          "description": "Which way to extend the stroke by one plot. Stepping onto the plot just behind the head lifts the ink (undo)."
        }
      },
      "required": [
        "type",
        "direction"
      ]
    },
    {
      "type": "object",
      "properties": {
        "type": {
          "const": "undo"
        }
      },
      "required": [
        "type"
      ],
      "description": "Lift the head plot off the stroke (+1 wasted step). Invalid when the stroke is only Stone 1."
    },
    {
      "type": "object",
      "properties": {
        "type": {
          "const": "reset"
        }
      },
      "required": [
        "type"
      ],
      "description": "Sweep the current garden clean, back to Stone 1 alone (+10 wasted steps)."
    },
    {
      "type": "object",
      "properties": {
        "type": {
          "const": "endRun"
        }
      },
      "required": [
        "type"
      ],
      "description": "End the run here and keep every banked point. The garden in progress banks nothing further and the Still Water bonus is not paid."
    }
  ]
}

Start a game

curl -s "https://gameboard.gg/api/games/sumi-steps/init?seed=7"

Then POST { state, action } to https://gameboard.gg/api/games/sumi-steps/action, carrying state forward each call. See the API overview for the full loop.