{
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    "frontier": "Stable custom binary min-heap ordered by total estimated cost, then insertion order.",
    "grid": "Rectangular bounded grid.",
    "heuristic": "Manhattan distance.",
    "movement_cost": "Every legal step costs one.",
    "neighbours": "Four cardinal neighbours in a fixed order.",
    "state": "Closed set, integer cost-so-far map, and parent reconstruction."
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  "artifact": "Standalone Godot GDScript A* pathfinding starter scene",
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        "expected_cell_count": 8,
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            "y": 0
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          {
            "x": 2,
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          {
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            "x": 4,
            "y": 1
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            "y": 2
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          {
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            "y": 3
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      "passed": true
    },
    {
      "id": "routes_around_blocked_cells_with_shortest_length",
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          {
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          {
            "x": 4,
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          {
            "x": 5,
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        ],
        "reference_bfs_steps": 16
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      "passed": true
    },
    {
      "id": "returns_empty_when_destination_is_unreachable",
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      },
      "passed": true
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          },
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          },
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            "y": 3
          },
          {
            "x": 5,
            "y": 2
          }
        ]
      },
      "passed": true
    },
    {
      "id": "path_never_enters_blocked_cells",
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        "blocked": [
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            "x": 2,
            "y": 1
          },
          {
            "x": 2,
            "y": 2
          },
          {
            "x": 2,
            "y": 3
          }
        ],
        "path": [
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            "y": 2
          },
          {
            "x": 1,
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          },
          {
            "x": 1,
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          },
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          {
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          },
          {
            "x": 5,
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          },
          {
            "x": 5,
            "y": 2
          }
        ]
      },
      "passed": true
    },
    {
      "id": "start_equals_goal_returns_single_cell",
      "observed": {
        "path": [
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            "x": 2,
            "y": 2
          }
        ]
      },
      "passed": true
    },
    {
      "id": "out_of_bounds_endpoints_return_empty",
      "observed": {
        "invalid_goal_path": [],
        "invalid_start_path": []
      },
      "passed": true
    },
    {
      "id": "heap_pops_lowest_priority_first",
      "observed": {
        "cells": [
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            "x": 2,
            "y": 0
          },
          {
            "x": 4,
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          },
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        ],
        "priorities": [
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          3,
          5,
          8
        ]
      },
      "passed": true
    },
    {
      "id": "runnable_scene_draws_path_moves_agent_and_shows_no_path",
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            "y": 4
          },
          "authored_scene_nodes": {
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            "status": true
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          "status": "Destination reached • click another cell or press R",
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        "authored_scene_complete": true,
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      "passed": true
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      "id": "packaged_project_reruns_cleanly",
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  "measurement_scope": "Deterministic baseline-path correctness and runnable-scene behavior only. No timing, FPS, memory, engine-comparison, or production-readiness claim.",
  "passed": true,
  "passed_count": 10,
  "proof_boundary": {
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  "verified_at": "2026-07-16T08:23:55",
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