SyncValsverifier → artifact → classifier → verdict
SyncVals · Trajectory

checkpoint-system

claude-code claude-opus-4-8 ✗ failed HARNESS_ERROR ↑ 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
HARNESS_ERRORInfrastructure failure, the agent never ran properly. Not a signal about agent or task.
SubtypeFile Persistence / Environment Issue
EvidenceAgent wrote complete, correct implementations to checkpoint.gd and checkpoint.tscn (steps 13-16 of trajectory show successful writes with metadata confirmation). However, the actual environment files used for testing remain unchanged from the template: checkpoint.gd still contains only 'extends Area2D / class_name Checkpoint / func _ready() -> void: pass' and checkpoint.tscn is bare '[gd_scene load_steps=1 format=3] / [node name=\"Checkpoint\" type=\"Area2D\"]'. Test fails with 'beacon export must be wired to the Beacon Sprite2D in the scene' because the script never received the exports and node references the agent implemented.
Root causeThe agent's file writes succeeded in their execution context but did not persist to the repository files used for verification. Either the write operations were applied to a temporary location, or the runner reverted changes before test execution.
RecommendationInvestigate the trial execution environment to determine why file writes are not persisting. Check: (1) whether the agent's working directory matches the repository root used for testing, (2) whether there is a filesystem remapping or isolation layer that prevents writes from persisting, (3) whether the runner is reverting the workspace before test execution. The agent's implementation is correct and complete; the task specification itself is fine."
Trajectory
Tool-by-tool agent trajectory
17 tool calls · 3 tool types · 17 steps
Build an animated checkpoint beacon for a 2D platformer. Create `scenes/checkpoint.tscn` with an `Area2D` root node named `Checkpoint` (attach `scripts/checkpoint.gd`). Give it these children: - a `CollisionShape2D` using a `RectangleShape2D` sized 32×32, - a `Sprite2D` named `Beacon` (the visual that pulses as the checkpoint charges), - a `Label` named `ChargeLabel`. Wire the area so bodies entering it reach the script's `_on_body_entered(body)` handler. In `scripts/checkpoint.gd`, implement the `Checkpoint` class: - Export an int `checkpoint_id` (default `0`) and a bool `is_final_checkpoint` (default `false`). Expose a public bool `is_active` (default `false`). - Export a `Gradient` resource named `charge_gradient`, authored in the scene with three color stops: offset `0.0` is deep blue `Color(0.1, 0.2, 0.6)`, offset `0.5` is bright cyan `Color(0.2, 0.9, 1.0)`, offset `1.0` is white `Color(1.0, 1.0, 1.0)`. - Export a `Curve` resource named `scale_curve`, authored so that sampling its baked value returns `1.0` at position `0.0`, `1.8` at position `0.5`, and `2.0` at position `1.0`. - Export a `Sprite2D` reference named `beacon` and a `Label` reference named `charge_label`, each wired in the scene to the `Beacon` and `ChargeLabel` nodes. Behavior: - `apply_charge(t: float)` drives the beacon's look for a charge fraction `t` in `[0, 1]`: set `beacon.modulate` to `charge_gradient` sampled at `t`, and set `beacon.scale` to `Vector2.ONE * scale_curve.sample_baked(t)`. - Only the player can light a checkpoint , the player belongs to the `"Player"` group; any other body that enters must be ignored. The first time the player reaches an unlit checkpoint, set it active, drive the beacon to full charge by calling `apply_charge(1.0)`, write the checkpoint's id into `charge_label.text`, and emit `activated` carrying `checkpoint_id`. While it stays lit, re-touching it does nothing. - A final checkpoint (`is_final_checkpoint == true`) must also emit `level_complete` at the moment it activates. - `reset()` re-arms the checkpoint (sets `is_active` back to false) so it can be lit again. Declare the signals `activated(id: int)` and `level_complete`.
I'll create both files. Let me write the script and the scene.
Write
{
  "file_path": "/home/user/task/scripts/checkpoint.gd",
  "content": "class_name Checkpoint\nextends Area2D\n\n## Emitted when the player first lights this checkpoint.\nsignal activated(id: int)\n## Emitted alongside activation when this is the level's final checkpoint.\nsignal level_complete\n\n@export var checkpoint_id: int = 0\n@export var is_final_checkpoint: bool = false\n\n## Drives the beacon color across the charge fraction.\n@export var charge_gradient: Gradient\n## Drives the beacon scale across the charge fraction.\n@export var scale_curve: Curve\n\n@export var beacon: Sprite2D\n@export var charge_label: Label\n\nvar is_active: bool = false\n\n\nfunc apply_charge(t: float) -> void:\n\tbeacon.modulate = charge_gradient.sample(t)\n\tbeacon.scale = Vector2.ONE * scale_curve.sample_baked(t)\n\n\nfunc reset() -> void:\n\tis_active = false\n\n\nfunc _on_body_entered(body: Node) -> void:\n\tif not body.is_in_group(\"Player\"):\n\t\treturn\n\tif is_active:\n\t\treturn\n\n\tis_active = true\n\tapply_charge(1.0)\n\tcharge_label.text = str(checkpoint_id)\n\tactivated.emit(checkpoint_id)\n\n\tif is_final_checkpoint:\n\t\tlevel_complete.emit()\n"
}
output
<tool_use_error>File has not been read yet. Read it first before writing to it.</tool_use_error>

[error] tool reported failure
Write
{
  "file_path": "/home/user/task/scenes/checkpoint.tscn",
  "content": "[gd_scene load_steps=5 format=3 uid=\"uid://c3kp0intbe4c0\"]\n\n[ext_resource type=\"Script\" path=\"res://scripts/checkpoint.gd\" id=\"1_script\"]\n\n[sub_resource type=\"RectangleShape2D\" id=\"RectangleShape2D_1\"]\nsize = Vector2(32, 32)\n\n[sub_resource type=\"Gradient\" id=\"Gradient_1\"]\noffsets = PackedFloat32Array(0, 0.5, 1)\ncolors = PackedColorArray(0.1, 0.2, 0.6, 1, 0.2, 0.9, 1, 1, 1, 1, 1, 1)\n\n[sub_resource type=\"Curve\" id=\"Curve_1\"]\nmax_value = 2.0\n_data = [Vector2(0, 1), 0.0, 0.0, 0, 0, Vector2(0.5, 1.8), 0.0, 0.0, 0, 0, Vector2(1, 2), 0.0, 0.0, 0, 0]\npoint_count = 3\n\n[node name=\"Checkpoint\" type=\"Area2D\"]\nscript = ExtResource(\"1_script\")\ncharge_gradient = SubResource(\"Gradient_1\")\nscale_curve = SubResource(\"Curve_1\")\nbeacon = NodePath(\"Beacon\")\ncharge_label = NodePath(\"ChargeLabel\")\n\n[node name=\"CollisionShape2D\" type=\"CollisionShape2D\" parent=\".\"]\nshape = SubResource(\"RectangleShape2D_1\")\n\n[node name=\"Beacon\" type=\"Sprite2D\" parent=\".\"]\n\n[node name=\"ChargeLabel\" type=\"Label\" parent=\".\"]\n\n[connection signal=\"body_entered\" from=\".\" to=\".\" method=\"_on_body_entered\"]\n"
}
output
<tool_use_error>File has not been read yet. Read it first before writing to it.</tool_use_error>

[error] tool reported failure
Files already exist. Let me read them first.
Read
{
  "file_path": "/home/user/task/scripts/checkpoint.gd"
}
output
1	extends Area2D
2	class_name Checkpoint
3	
4	func _ready() -> void:
5		pass
6
Read
{
  "file_path": "/home/user/task/scenes/checkpoint.tscn"
}
output
1	[gd_scene load_steps=1 format=3]
2	
3	[node name="Checkpoint" type="Area2D"]
4
Now I'll overwrite both with the full implementation.
Write
{
  "file_path": "/home/user/task/scripts/checkpoint.gd",
  "content": "class_name Checkpoint\nextends Area2D\n\n## Emitted when the player first lights this checkpoint.\nsignal activated(id: int)\n## Emitted alongside activation when this is the level's final checkpoint.\nsignal level_complete\n\n@export var checkpoint_id: int = 0\n@export var is_final_checkpoint: bool = false\n\n## Drives the beacon color across the charge fraction.\n@export var charge_gradient: Gradient\n## Drives the beacon scale across the charge fraction.\n@export var scale_curve: Curve\n\n@export var beacon: Sprite2D\n@export var charge_label: Label\n\nvar is_active: bool = false\n\n\nfunc apply_charge(t: float) -> void:\n\tbeacon.modulate = charge_gradient.sample(t)\n\tbeacon.scale = Vector2.ONE * scale_curve.sample_baked(t)\n\n\nfunc reset() -> void:\n\tis_active = false\n\n\nfunc _on_body_entered(body: Node) -> void:\n\tif not body.is_in_group(\"Player\"):\n\t\treturn\n\tif is_active:\n\t\treturn\n\n\tis_active = true\n\tapply_charge(1.0)\n\tcharge_label.text = str(checkpoint_id)\n\tactivated.emit(checkpoint_id)\n\n\tif is_final_checkpoint:\n\t\tlevel_complete.emit()\n"
}
output
The file /home/user/task/scripts/checkpoint.gd has been updated successfully. (file state is current in your context , no need to Read it back)
Write
{
  "file_path": "/home/user/task/scenes/checkpoint.tscn",
  "content": "[gd_scene load_steps=5 format=3 uid=\"uid://c3kp0intbe4c0\"]\n\n[ext_resource type=\"Script\" path=\"res://scripts/checkpoint.gd\" id=\"1_script\"]\n\n[sub_resource type=\"RectangleShape2D\" id=\"RectangleShape2D_1\"]\nsize = Vector2(32, 32)\n\n[sub_resource type=\"Gradient\" id=\"Gradient_1\"]\noffsets = PackedFloat32Array(0, 0.5, 1)\ncolors = PackedColorArray(0.1, 0.2, 0.6, 1, 0.2, 0.9, 1, 1, 1, 1, 1, 1)\n\n[sub_resource type=\"Curve\" id=\"Curve_1\"]\nmax_value = 2.0\n_data = [Vector2(0, 1), 0.0, 0.0, 0, 0, Vector2(0.5, 1.8), 0.0, 0.0, 0, 0, Vector2(1, 2), 0.0, 0.0, 0, 0]\npoint_count = 3\n\n[node name=\"Checkpoint\" type=\"Area2D\"]\nscript = ExtResource(\"1_script\")\ncharge_gradient = SubResource(\"Gradient_1\")\nscale_curve = SubResource(\"Curve_1\")\nbeacon = NodePath(\"Beacon\")\ncharge_label = NodePath(\"ChargeLabel\")\n\n[node name=\"CollisionShape2D\" type=\"CollisionShape2D\" parent=\".\"]\nshape = SubResource(\"RectangleShape2D_1\")\n\n[node name=\"Beacon\" type=\"Sprite2D\" parent=\".\"]\n\n[node name=\"ChargeLabel\" type=\"Label\" parent=\".\"]\n\n[connection signal=\"body_entered\" from=\".\" to=\".\" method=\"_on_body_entered\"]\n"
}
output
The file /home/user/task/scenes/checkpoint.tscn has been updated successfully. (file state is current in your context , no need to Read it back)
Done. Both files are implemented. **`scripts/checkpoint.gd`** , the `Checkpoint` class: - Signals `activated(id: int)` and `level_complete`. - Exports: `checkpoint_id` (int, 0), `is_final_checkpoint` (bool, false), `charge_gradient`, `scale_curve`, `beacon`, `charge_label`; plus public `is_active` (false). - `apply_charge(t)` sets `beacon.modulate` from the gradient and `beacon.scale` from the baked curve. - `_on_body_entered` ignores non-`"Player"` bodies and already-lit checkpoints; on first player touch it lights up, charges to full, writes the id to the label, emits `activated`, and additionally emits `level_complete` when final. - `reset()` re-arms it. **`scenes/checkpoint.tscn`** , `Area2D` root `Checkpoint` with the script attached and `body_entered` connected to `_on_body_entered`. Children: `CollisionShape2D` (32×32 `RectangleShape2D`), `Sprite2D` "Beacon", `Label` "ChargeLabel". The `beacon`/`charge_label` exports point at those nodes. Two authoring details worth flagging: - The `Gradient` sub-resource carries the three stops exactly as specified (deep blue → cyan → white). - The `Curve` needs `max_value = 2.0` set explicitly , Godot's default curve range is `[0, 1]`, so without raising the ceiling the `1.8` and `2.0` points would be silently clamped to `1.0`. With it, `sample_baked` returns `1.0 / 1.8 / 2.0` at positions `0.0 / 0.5 / 1.0`. A caveat I can't fully verify without the editor: the exact byte-level format of the embedded `Gradient`/`Curve` resources. The values are correct, but Godot may rewrite/normalize these sub-resources (and assign a real UID) the first time you open the scene , that's expected and harmless.
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: beacon export must be wired to the Beacon Sprite2D in the scene

Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_7211ba0463c64823. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.

Trial trial_7211ba0463c64823 · verifier authoritative; classifier explanatory.