SyncValsverifier → artifact → classifier → verdict
SyncVals · Trajectory

tile-gradient-particles

claude-code claude-sonnet-4-6 ✗ failed BAD_FAILURE ↑ View task
Solved from the instruction alone, tests/ and solution/ were withheld from the agent's workspace and restored only for grading.
Reward = tests/test.sh exit code (0 → resolved); the classification below is post-hoc and cannot change it.
Classification , post-hoc; cannot change the reward
BAD_FAILUREThe task is at fault, underspecified/contradictory instruction, brittle/flaky tests, or tests demanding undiscoverable behavior.
SubtypeUnderspecified Instruction
EvidenceTest error: "Tank: LeftTrackParticles color_ramp must be set to a gradient when moving". The instruction states to "assign it to each emitter's `process_material.color_ramp`" where "it" refers to the GradientTexture1D exports. However, `color_ramp` property expects a `Gradient` object, not a `GradientTexture1D`. The agent correctly followed the instruction's wording but this resulted in assigning the wrong type. The fix requires extracting `gradient_texture.gradient` to get the Gradient, which is not mentioned in the instruction.
Root causeThe instruction conflates GradientTexture1D (the correct export type for the UI/resources) with what should be assigned to color_ramp (the underlying Gradient object). The instruction says to export GradientTexture1D but then assign "it" directly to color_ramp, which requires extracting the Gradient from the GradientTexture1D, a critical step the instruction omits.
RecommendationClarify the instruction to specify that the GradientTexture1D should be exported for the resource pipeline, but in the _update_track_particles() method, the code should extract the Gradient from the GradientTexture1D before assigning: `left_track_particles.process_material.color_ramp = gradient.gradient` (assuming 'gradient' is the GradientTexture1D)."
Trajectory
Tool-by-tool agent trajectory
9 tool calls · 3 tool types · 13 steps
# Track Particles Driven by Tile Type Gradient In `scenes/world.tscn`, add a TileSet custom data layer named `tile_type` with type int, and assign GradientTexture1D exports named `water_color`, `dirt_color`, and `grass_color` on the World node. In `scripts/world.gd`, add `enum TILE_TYPES { NONE, WATER, DIRT, GRASS }`, export the three GradientTexture1D variables (`water_color`, `dirt_color`, `grass_color`), create a dictionary mapping TILE_TYPES enum members to those gradients, and add a static `get_gradient_at(position)` that reads `get_custom_data_at(position, "tile_type")` and returns the matching gradient. In `scenes/tank.tscn`, add `LeftTrackParticles` and `RightTrackParticles` GPUParticles2D nodes configured to produce realistic track dust trails , use box emission, set directional flow in opposite vertical directions for left and right tracks, configure appropriate spread, disable gravity, set reasonable velocity and damping, use small particle scale, set amount and z_index appropriately, and start with emitting disabled. In `scripts/tank.gd`, track the current particle gradient using `World.get_gradient_at(position)`, assign it to each emitter's `process_material.color_ramp`, set both emitters to `emitting = true` while moving, and `emitting = false` when not moving, via a method named `_update_track_particles`.
Let me explore the project structure first.

List all files in the task directory

shell
find /home/user/task -type f | sort
output
/home/user/task/.godot/.gdignore
/home/user/task/.godot/editor/filesystem_cache10
/home/user/task/.godot/editor/main.tscn-folding-3ad5c15c4f3250da0cc7c1af1770d85f.cfg
/home/user/task/.godot/editor/project_metadata.cfg
/home/user/task/.godot/global_script_class_cache.cfg
/home/user/task/.godot/imported/tank_body.png-a051a2ed122e9e86f36df226d2426b35.ctex
/home/user/task/.godot/imported/tank_body.png-a051a2ed122e9e86f36df226d2426b35.md5
/home/user/task/.godot/imported/terrain.png-dfc2a3dbab29348c6bdbbce57351be83.ctex
/home/user/task/.godot/imported/terrain.png-dfc2a3dbab29348c6bdbbce57351be83.md5
/home/user/task/.godot/scene_groups_cache.cfg
/home/user/task/.godot/uid_cache.bin
/home/user/task/assets/sprites/tank_body.png
/home/user/task/assets/sprites/tank_body.png.import
/home/user/task/assets/sprites/terrain.png
/home/user/task/assets/sprites/terrain.png.import
/home/user/task/project.godot
/home/user/task/scenes/main.tscn
/home/user/task/scenes/tank.tscn
/home/user/task/scenes/test.tscn
/home/user/task/scenes/world.tscn
/home/user/task/scripts/tank.gd
/home/user/task/scripts/tank.gd.uid
/home/user/task/scripts/test.gd
/home/user/task/scripts/test.gd.uid
/home/user/task/scripts/world.gd
/home/user/task/scripts/world.gd.uid

[stdout]
/home/user/task/.godot/.gdignore
/home/user/task/.godot/editor/filesystem_cache10
/home/user/task/.godot/editor/main.tscn-folding-3ad5c15c4f3250da0cc7c1af1770d85f.cfg
/home/user/task/.godot/editor/project_metadata.cfg
/home/user/task/.godot/global_script_class_cache.cfg
/home/user/task/.godot/imported/tank_body.png-a051a2ed122e9e86f36df226d2426b35.ctex
/home/user/task/.godot/imported/tank_body.png-a051a2ed122e9e86f36df226d2426b35.md5
/home/user/task/.godot/imported/terrain.png-dfc2a3dbab29348c6bdbbce57351be83.ctex
/home/user/task/.godot/imported/terrain.png-dfc2a3dbab29348c6bdbbce57351be83.md5
/home/user/task/.godot/scene_groups_cache.cfg
/home/user/task/.godot/uid_cache.bin
/home/user/task/assets/sprites/tank_body.png
/home/user/task/assets/sprites/tank_body.png.import
/home/user/task/assets/sprites/terrain.png
/home/user/task/assets/sprites/terrain.png.import
/home/user/task/project.godot
/home/user/task/scenes/main.tscn
/home/user/task/scenes/tank.tscn
/home/user/task/scenes/test.tscn
/home/user/task/scenes/world.tscn
/home/user/task/scripts/tank.gd
/home/user/task/scripts/tank.gd.uid
/home/user/task/scripts/test.gd
/home/user/task/scripts/test.gd.uid
/home/user/task/scripts/world.gd
/home/user/task/scripts/world.gd.uid

/home/user/task/scenes/world.tscn

contents
1	[gd_scene load_steps=3 format=3 uid="uid://world_start_1218"]
2	
3	[ext_resource type="Script" path="res://scripts/world.gd" id="1_world"]
4	
5	[sub_resource type="TileSet" id="TileSet_world"]
6	
7	[node name="World" type="Node2D"]
8	script = ExtResource("1_world")
9	
10	[node name="TileMap" type="TileMap" parent="."]
11	tile_set = SubResource("TileSet_world")
12	format = 2
13	layer_0/name = "terrain"
14	layer_0/z_index = -10
15

/home/user/task/scripts/world.gd

contents
1	extends Node2D
2	class_name World
3	
4	@onready var tile_map: TileMap = $TileMap
5	
6	static var _instance: World = null
7	
8	func _ready():
9		if _instance == null:
10			_instance = self
11	
12	
13	static func get_tile_data_at(position: Vector2) -> TileData:
14		var local_position: Vector2i = _instance.tile_map.local_to_map(position)
15		return _instance.tile_map.get_cell_tile_data(0, local_position)
16	
17	
18	static func get_custom_data_at(position: Vector2, custom_data_name: String) -> Variant:
19		var data = get_tile_data_at(position)
20		if data == null:
21			return null
22		return data.get_custom_data(custom_data_name)
23

/home/user/task/scripts/tank.gd

contents
1	extends CharacterBody2D
2	class_name Tank
3	
4	const SPEED = 64.0
5	const TURN_SPEED = 2.0
6	
7	var direction := Vector2.RIGHT
8	
9	func _physics_process(delta):
10		var drive_input := 0.0
11		var turn_input := 0.0
12		if InputMap.has_action("move_backward") and InputMap.has_action("move_forward"):
13			drive_input = Input.get_axis("move_backward", "move_forward")
14		if InputMap.has_action("turn_left") and InputMap.has_action("turn_right"):
15			turn_input = Input.get_axis("turn_left", "turn_right")
16		if turn_input != 0.0:
17			direction = direction.rotated(turn_input * (PI / 2.0) * TURN_SPEED * delta)
18			rotation = direction.angle()
19		if drive_input != 0.0:
20			velocity = direction.normalized() * drive_input * SPEED
21		else:
22			velocity = Vector2.ZERO
23		move_and_slide()
24

/home/user/task/scenes/tank.tscn

contents
1	[gd_scene load_steps=3 format=3 uid="uid://tank_start_1218"]
2	
3	[ext_resource type="Script" path="res://scripts/tank.gd" id="1_tank_script"]
4	
5	[sub_resource type="RectangleShape2D" id="RectangleShape2D_1"]
6	size = Vector2(26, 26)
7	
8	[node name="Tank" type="CharacterBody2D"]
9	script = ExtResource("1_tank_script")
10	
11	[node name="BodySprite" type="Sprite2D" parent="."]
12	
13	[node name="CollisionShape2D" type="CollisionShape2D" parent="."]
14	shape = SubResource("RectangleShape2D_1")
15
Now I have a full picture of the project. Let me implement all four changes.
write · /home/user/task/scenes/world.tscn
[gd_scene load_steps=9 format=3 uid="uid://world_start_1218"]

[ext_resource type="Script" path="res://scripts/world.gd" id="1_world"]

[sub_resource type="TileSet" id="TileSet_world"]
custom_data_layer_0/name = "tile_type"
custom_data_layer_0/type = 2

[sub_resource type="Gradient" id="Gradient_water"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.3, 0.5, 0.8, 0.8, 0.1, 0.2, 0.5, 0)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_water"]
gradient = SubResource("Gradient_water")

[sub_resource type="Gradient" id="Gradient_dirt"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.6, 0.4, 0.2, 0.8, 0.8, 0.65, 0.4, 0)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_dirt"]
gradient = SubResource("Gradient_dirt")

[sub_resource type="Gradient" id="Gradient_grass"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.2, 0.5, 0.1, 0.8, 0.4, 0.6, 0.2, 0)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_grass"]
gradient = SubResource("Gradient_grass")

[node name="World" type="Node2D"]
script = ExtResource("1_world")
water_color = SubResource("GradientTexture1D_water")
dirt_color = SubResource("GradientTexture1D_dirt")
grass_color = SubResource("GradientTexture1D_grass")

[node name="TileMap" type="TileMap" parent="."]
tile_set = SubResource("TileSet_world")
format = 2
layer_0/name = "terrain"
layer_0/z_index = -10
write · /home/user/task/scripts/world.gd
extends Node2D
class_name World

enum TILE_TYPES { NONE, WATER, DIRT, GRASS }

@export var water_color: GradientTexture1D
@export var dirt_color: GradientTexture1D
@export var grass_color: GradientTexture1D

@onready var tile_map: TileMap = $TileMap

static var _instance: World = null

func _ready():
	if _instance == null:
		_instance = self


static func get_tile_data_at(position: Vector2) -> TileData:
	var local_position: Vector2i = _instance.tile_map.local_to_map(position)
	return _instance.tile_map.get_cell_tile_data(0, local_position)


static func get_custom_data_at(position: Vector2, custom_data_name: String) -> Variant:
	var data = get_tile_data_at(position)
	if data == null:
		return null
	return data.get_custom_data(custom_data_name)


static func get_gradient_at(position: Vector2) -> GradientTexture1D:
	if _instance == null:
		return null
	var tile_type = get_custom_data_at(position, "tile_type")
	var gradient_map := {
		TILE_TYPES.WATER: _instance.water_color,
		TILE_TYPES.DIRT: _instance.dirt_color,
		TILE_TYPES.GRASS: _instance.grass_color,
	}
	return gradient_map.get(tile_type, null)
write · /home/user/task/scenes/tank.tscn
[gd_scene load_steps=5 format=3 uid="uid://tank_start_1218"]

[ext_resource type="Script" path="res://scripts/tank.gd" id="1_tank_script"]

[sub_resource type="RectangleShape2D" id="RectangleShape2D_1"]
size = Vector2(26, 26)

[sub_resource type="ParticleProcessMaterial" id="ParticleProcessMaterial_left"]
resource_local_to_scene = true
emission_shape = 3
emission_box_extents = Vector3(8.0, 1.0, 0.0)
direction = Vector3(0.0, -1.0, 0.0)
spread = 20.0
initial_velocity_min = 15.0
initial_velocity_max = 25.0
damping_min = 15.0
damping_max = 25.0
gravity = Vector3(0.0, 0.0, 0.0)
scale_min = 0.3
scale_max = 0.8

[sub_resource type="ParticleProcessMaterial" id="ParticleProcessMaterial_right"]
resource_local_to_scene = true
emission_shape = 3
emission_box_extents = Vector3(8.0, 1.0, 0.0)
direction = Vector3(0.0, 1.0, 0.0)
spread = 20.0
initial_velocity_min = 15.0
initial_velocity_max = 25.0
damping_min = 15.0
damping_max = 25.0
gravity = Vector3(0.0, 0.0, 0.0)
scale_min = 0.3
scale_max = 0.8

[node name="Tank" type="CharacterBody2D"]
script = ExtResource("1_tank_script")

[node name="BodySprite" type="Sprite2D" parent="."]

[node name="CollisionShape2D" type="CollisionShape2D" parent="."]
shape = SubResource("RectangleShape2D_1")

[node name="LeftTrackParticles" type="GPUParticles2D" parent="."]
position = Vector2(-6, -10)
z_index = -1
amount = 16
lifetime = 0.6
process_material = SubResource("ParticleProcessMaterial_left")
local_coords = false
emitting = false

[node name="RightTrackParticles" type="GPUParticles2D" parent="."]
position = Vector2(-6, 10)
z_index = -1
amount = 16
lifetime = 0.6
process_material = SubResource("ParticleProcessMaterial_right")
local_coords = false
emitting = false
write · /home/user/task/scripts/tank.gd
extends CharacterBody2D
class_name Tank

const SPEED = 64.0
const TURN_SPEED = 2.0

var direction := Vector2.RIGHT
var _current_gradient: GradientTexture1D = null

@onready var left_track_particles: GPUParticles2D = $LeftTrackParticles
@onready var right_track_particles: GPUParticles2D = $RightTrackParticles

func _physics_process(delta):
	var drive_input := 0.0
	var turn_input := 0.0
	if InputMap.has_action("move_backward") and InputMap.has_action("move_forward"):
		drive_input = Input.get_axis("move_backward", "move_forward")
	if InputMap.has_action("turn_left") and InputMap.has_action("turn_right"):
		turn_input = Input.get_axis("turn_left", "turn_right")
	if turn_input != 0.0:
		direction = direction.rotated(turn_input * (PI / 2.0) * TURN_SPEED * delta)
		rotation = direction.angle()
	if drive_input != 0.0:
		velocity = direction.normalized() * drive_input * SPEED
	else:
		velocity = Vector2.ZERO
	move_and_slide()
	_update_track_particles()


func _update_track_particles() -> void:
	var gradient := World.get_gradient_at(global_position)
	if gradient != _current_gradient:
		_current_gradient = gradient
		left_track_particles.process_material.color_ramp = gradient
		right_track_particles.process_material.color_ramp = gradient
	var is_moving := velocity != Vector2.ZERO
	left_track_particles.emitting = is_moving
	right_track_particles.emitting = is_moving
All four files updated. Here's a summary of what was done: **`scenes/world.tscn`** , Added `custom_data_layer_0` (`tile_type`, type int=2) to the TileSet. Added three `Gradient` + `GradientTexture1D` sub-resources (water=blues, dirt=browns, grass=greens, each fading to transparent) and assigned them to the World node. **`scripts/world.gd`** , Added `enum TILE_TYPES { NONE, WATER, DIRT, GRASS }`, three `@export var` GradientTexture1D fields, and `static func get_gradient_at()` which reads `tile_type` custom data and returns the matching gradient via a local dictionary keyed on enum values. **`scenes/tank.tscn`** , Added two `ParticleProcessMaterial` sub-resources (both using box emission, 20° spread, no gravity, velocity 15–25, damping 15–25, scale 0.3–0.8, `resource_local_to_scene = true`) with directions `Vector3(0, -1, 0)` and `Vector3(0, 1, 0)` for opposite lateral flow. Added `LeftTrackParticles` (position `(-6, -10)`, z_index -1, local_coords false, emitting false) and `RightTrackParticles` (position `(-6, 10)`) as children of Tank. **`scripts/tank.gd`** , Added `_current_gradient` tracking var, `@onready` refs to both particle nodes, and `_update_track_particles()` which fetches the gradient, assigns it to both `process_material.color_ramp` only when changed, and toggles `emitting` based on whether velocity is non-zero.
Final diff , what the agent changed

No file changes, the agent left the workspace untouched.

Verifier output , the proof behind the reward
tests/test.sh
Godot Engine v4.4.stable.official.4c311cbee - https://godotengine.org
WARNING: Started the engine as `root`/superuser. This is a security risk, and subsystems like audio may not work correctly.
Set the environment variable `GODOT_SILENCE_ROOT_WARNING` to 1 to silence this warning.
     at: setup2 (main/main.cpp:3181)

VALIDATION_FAILED: Tank: LeftTrackParticles color_ramp must be set to a gradient when moving

Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_fd1e9d1f2ffb4ed1. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.

Trial trial_fd1e9d1f2ffb4ed1 · verifier authoritative; classifier explanatory.