SyncValsverifier → artifact → classifier → verdict
SyncVals · Trajectory

adv-robust-pgd

claude-code claude-opus-4-8 ✗ failed GOOD_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
GOOD_FAILUREHonest miss, the agent ran correctly but couldn't solve it. Expected for a hard task; the task is sound.
SubtypeInsufficient Exploration / Hyperparameter Tuning
EvidenceComponent Conformance Suite: 201/201 cases passed (all milestones: True); Final Metric: PGD robust accuracy = 0.5675 < threshold 0.6. Verifier note confirms framework correctness and e2b OOM artifact. Agent's train.py executed successfully on re-grade with 24GB memory. The 3.25 percentage-point shortfall (56.75% vs 60%) indicates the framework is correct but training hyperparameters (perturbation budget, training steps, adversarial-training recipe strength) need tuning to reach the threshold.
Root causeThe agent correctly implemented the entire numpy deep-learning framework and adversarial-training pipeline (201/201 component checks pass), but the trained model's robust accuracy fell just below the threshold. This is a hyperparameter/training-recipe optimization problem, not a framework bug or specification issue.
RecommendationN/A - task is fine. The framework specification is clear, the tests are reasonable (grader owns the attack with no access to agent code), and all 201 component checks passed. The failure is due to insufficient training robustness, which is expected for this hard domain. The agent would need to experiment with higher training-time perturbation budgets (matching the eval epsilon), more PGD steps, longer training, or stronger adversarial-training recipes (e.g., TRADES with higher beta coefficient, or MART) to close the 3.25pp gap.
Trajectory
Tool-by-tool agent trajectory
120 tool calls · 4 tool types · 141 steps
Agent session started, model: claude-opus-4-8 · 29 tools available · cwd: /app
I'll start by exploring the structure and understanding what's stubbed out.
shell
ls -la && echo "---SUBMISSION---" && ls -la submission/ && echo "---DATA---" && ls -la data/ && python3 -c "import numpy as np; d=np.load('data/train.npz'); print({k:(v.shape,v.dtype) for k,v in d.items()}); print('y unique', np.unique(d['y']))"
output
total 101
drwxr-xr-x  4 user user  4096 Jun 30 22:29 .
drwxr-xr-x 21 root root  4096 Jun 30 22:28 ..
-rw-r--r--  1 user user 14238 Jun 30 22:29 PROMPT.txt
-rw-r--r--  1 user user     5 Jun 30 22:29 agent.pid
-rw-r--r--  1 user user     0 Jun 30 22:29 agent.stderr
-rw-r--r--  1 user user  4625 Jun 30 22:29 agent_trajectory.jsonl
drwxr-xr-x  2 user user    60 Jun 30 22:29 data
-rw-r--r--  1 user user     0 Jun 30 22:29 run.log
-rwxr-xr-x  1 user user 57740 Jun 30 11:01 run_checks.py
drwxr-xr-x  2 user user   128 Jun 30 22:29 submission
-rwxr-xr-x  1 user user   998 Jun 30 11:01 test.sh
-rwxr-xr-x  1 user user   629 Jun 30 11:01 timer.sh
---SUBMISSION---
total 80
drwxr-xr-x 2 user user   128 Jun 30 22:29 .
drwxr-xr-x 4 user user  4096 Jun 30 22:29 ..
-rw-r--r-- 1 user user  5490 Jun 30 11:01 advtrain.py
-rw-r--r-- 1 user user  8776 Jun 30 11:01 attack.py
-rw-r--r-- 1 user user 18341 Jun 30 11:01 autograd.py
-rw-r--r-- 1 user user  2167 Jun 30 11:01 data.py
-rw-r--r-- 1 user user 15988 Jun 30 11:01 nn.py
-rw-r--r-- 1 user user  8853 Jun 30 11:01 optim.py
-rw-r--r-- 1 user user  3742 Jun 30 11:01 train.py
---DATA---
total 2904
drwxr-xr-x 2 user user      60 Jun 30 22:29 .
drwxr-xr-x 4 user user    4096 Jun 30 22:29 ..
-rw-r--r-- 1 user user 2967336 Jun 30 11:01 train.npz
{'X': ((3600, 1, 16, 16), dtype('float32')), 'y': ((3600,), dtype('int64'))}
y unique [0 1 2 3 4 5]
I'll read all the stub files to understand the contracts.

/app/submission/autograd.py

contents
1	"""Reverse-mode automatic differentiation over numpy arrays (IMPLEMENT THIS).
2	
3	A ``Tensor`` wraps a single ``numpy.ndarray`` (``float64``) and records the operation that
4	produced it so that ``.backward()`` can walk the graph in reverse-topological order and
5	accumulate ``.grad`` (the gradient of the scalar on which ``.backward()`` was called w.r.t.
6	this tensor) into every leaf.
7	
8	This task is ADVERSARIAL ROBUSTNESS: the model is a small convolutional classifier and the
9	attacks (PGD/FGSM/MI-FGSM/PGD-L2/CW) ascend on the gradient of an attack loss w.r.t. the INPUT
10	image, so the autograd engine must (a) flow gradients back to PARAMETERS (for training) AND
11	(b) flow gradients back to the INPUT tensor (for the attack). BOTH directions are exercised by the
12	verifier's finite-difference gradient checks, so the convolution's input-gradient (the ``_col2im``
13	adjoint) is load-bearing.
14	
15	Contract (the verifier's conformance suite differentiates your analytic backward against finite
16	differences and checks your forward against its own reference, so match this exactly):
17	
18	* ``Tensor(data, requires_grad=False)`` -- ``data`` is array-like, stored as ``float64`` in
19	  ``self.data``; ``self.grad`` starts as ``None`` and becomes a same-shape ``float64`` array after
20	  backward. ``requires_grad`` leaves accumulate grad; non-requiring leaves do not.
21	* Every op returns a NEW ``Tensor`` whose ``requires_grad`` is the OR of its differentiable inputs.
22	 
…[truncated 18629 chars]
Now let me read the other files.

/app/submission/nn.py

contents
1	"""Neural-network layers + a small convolutional classifier, built on the autograd engine
2	(IMPLEMENT THE FORWARDS).
3	
4	Every module exposes ``params()`` -> list[Tensor] (the leaf tensors with ``requires_grad=True``)
5	and ``named_params()`` -> dict[str, Tensor] with STABLE names that match the checkpoint format the
6	verifier loads. ``SmallCNN.state_dict()`` / ``load_state_dict()`` round-trip a plain
7	``dict[str, np.ndarray]`` (saved as an ``.npz``); the verifier loads YOUR checkpoint into its OWN
8	reference SmallCNN via these names, so the names + shapes below are part of the contract.
9	
10	Naming contract for SmallCNN (do not change -- the verifier indexes by these exact keys):
11	  conv1.weight   (C1, C_in, 3, 3)        conv1.bias   (C1,)
12	  conv2.weight   (C2, C1, 3, 3)          conv2.bias   (C2,)
13	  fc1.weight     (C2*(H/4)*(W/4), F)      fc1.bias     (F,)
14	  fc2.weight     (F, n_classes)           fc2.bias     (n_classes,)
15	
16	Architecture (pinned): for an (N, C_in, H, W) input image batch,
17	  conv1 (C_in->C1, 3x3, pad 1) -> relu
18	  maxpool 2x2                   (H,W -> H/2,W/2)
19	  conv2 (C1->C2, 3x3, pad 1)   -> relu
20	  maxpool 2x2                   (H/2,W/2 -> H/4,W/4)
21	  flatten -> fc1 (-> F) -> relu -> fc2 (-> n_classes)   logits.
22	``Linear`` computes ``x @ weight + bias`` (weight is (in, out)). No BatchNorm inside SmallCNN (so
23	the attack runs a single deterministic eval-mode forward with no running-stat dependence).
24	
25	The other
…[truncated 15896 chars]

/app/submission/optim.py

contents
1	"""Optimizers + LR schedulers over a flat list of autograd ``Tensor`` parameters (IMPLEMENT THESE).
2	
3	Every optimizer operates IN PLACE on ``param.data`` using ``param.grad`` (the gradient accumulated
4	by ``Tensor.backward``). ``zero_grad()`` resets every grad to None. The EXACT update formula each
5	optimizer must match (the verifier checks one and several steps against its own reference) is in
6	its docstring.
7	
8	The adversarial-training loop uses AdamW (decoupled decay, with ``no_decay_ndim`` excluding 1-D
9	params/biases) + global grad-norm clipping; the rest of the optimizer zoo + the four LR schedulers
10	are part of the from-scratch framework the conformance suite audits.
11	"""
12	from __future__ import annotations
13	
14	import math
15	from typing import List
16	
17	import numpy as np
18	
19	from autograd import Tensor
20	
21	
22	class Optimizer:
23	    def __init__(self, params: List[Tensor]):
24	        self.params = list(params)
25	
26	    def zero_grad(self):
27	        for p in self.params:
28	            p.grad = None
29	
30	
31	class SGD(Optimizer):
32	    """SGD + momentum + optional Nesterov + (coupled/L2) weight decay:
33	        g = grad + wd*param;  v = mu*v + g;  step = (g + mu*v) if nesterov else v;  param -= lr*step."""
34	
35	    def __init__(self, params, lr=0.1, momentum=0.0, weight_decay=0.0, nesterov=False):
36	        super().__init__(params)
37	        self.lr = lr
38	        self.momentum = momentum
39	        self.weight_decay = weight
…[truncated 8125 chars]

/app/submission/attack.py

contents
1	"""White-box evasion attacks built on the from-scratch autograd engine (IMPLEMENT THESE).
2	
3	An adversary perturbs each input within a norm budget (L-inf eps in the [0,1] pixel domain by
4	default) and tries to make the classifier WRONG. Every attack ascends on the gradient of an attack
5	loss with respect to the INPUT image, which is exactly the gradient the autograd engine produces
6	when the input is wrapped in a ``requires_grad=True`` Tensor and the loss is backpropagated -- so a
7	correct ``conv2d`` input-gradient (the ``_col2im`` adjoint) is load-bearing.
8	
9	THE PRIMITIVE
10	  input_grad(model, x, y)                  d/dx of mean cross-entropy of model(x) vs y (ndarray).
11	  loss_input_grad(model, x, y, loss_fn)    d/dx of an ARBITRARY scalar attack loss loss_fn(logits,y).
12	
13	L-INF ATTACKS
14	  fgsm(model, x, y, eps)                    clip(x + eps*sign(input_grad)).
15	  pgd_attack(model, x, y, eps, steps, alpha)  iterated FGSM with random start + project to the
16	                                            L-inf eps-ball around x AND the [0,1] box each step.
17	  mi_fgsm(model, x, y, eps, steps, alpha, mu) momentum-iterative FGSM: accumulate a decaying
18	                                            momentum of the L1-NORMALIZED gradient, step on its sign,
19	                                            project each step.
20	  targeted_pgd(model, x, y_target, eps, steps, alpha)  DESCEND CE toward y_target (step on the
21	                                     
…[truncated 7820 chars]

/app/submission/advtrain.py

contents
1	"""Adversarial-training objectives built on the from-scratch autograd engine (IMPLEMENT THESE).
2	
3	Several standard recipes turn a fragile classifier into a robust one. Each crafts adversarial
4	inputs per minibatch with the model's own attack, then takes a gradient step on a robustness-aware
5	loss; the recipes differ in the loss. All run a single forward+backward; the caller does grad-clip
6	+ the optimizer step. ``x_clean`` / ``x_adv`` are ndarrays (N, C, H, W); ``y`` is an int (N,).
7	
8	  pgd_at_loss(model, x_adv, y)                  Madry PGD-AT: CE on the ADVERSARIAL batch.
9	  trades_loss(model, x_clean, x_adv, y, beta)   TRADES: CE(clean) + beta*KL(stopgrad(clean)||adv).
10	                                                The clean branch INSIDE the KL is a STOP-GRADIENT
11	                                                target (detached): the KL backprops only through
12	                                                the adversarial branch.
13	  mart_loss(model, x_clean, x_adv, y, beta)     MART: boosted-CE on the adversarial batch
14	                                                ( CE(adv,y) - mean log(1 - max_{j!=y} p_adv_j) ) +
15	                                                beta * mean_i[ (1 - p_clean_i[y_i]) *
16	                                                KL_i(softmax(adv)||stopgrad softmax(clean)) ].
17	  alp_loss(model, x_clean, x_adv, y, lam)       Adversarial Logit Pairing:
18	                                                0.5*(CE(clean)+CE(ad
…[truncated 4278 chars]

/app/submission/data.py

contents
1	"""Data loading + minibatching for the shape-classification set (IMPLEMENT THESE).
2	
3	The visible train split ships as ``/app/data/train.npz`` with arrays ``X`` (N, C, H, W) float
4	pixels in [0,1] and ``y`` (N,) int labels. The SEALED held-out split is NOT in the image -- the
5	verifier regenerates it from a secret feature seed and runs its own attack on it.
6	
7	Contract:
8	  load_npz(path) -> (X float64 (N,C,H,W), y int64 (N,))
9	  train_val_split(X, y, val_frac, rng) -> ((Xtr,ytr),(Xval,yval))   random disjoint split (val slice
10	        is a held-BACK slice of the VISIBLE train data you may use for best-checkpoint selection --
11	        it is NOT the verifier's sealed held-out set)
12	  iter_batches(X, y, batch_size, rng) -> yields (xb, yb) random-permutation minibatches
13	  get_batch(X, y, batch_size, rng) -> a single random minibatch
14	  to_onehot(y, n_classes) -> (N, n_classes) one-hot float matrix
15	  clip01(X) -> X clamped into the [0,1] pixel domain
16	"""
17	from __future__ import annotations
18	
19	from typing import Iterator, Tuple
20	
21	import numpy as np
22	
23	
24	def load_npz(path: str) -> Tuple[np.ndarray, np.ndarray]:
25	    raise NotImplementedError("implement load_npz")
26	
27	
28	def train_val_split(X: np.ndarray, y: np.ndarray, val_frac: float,
29	                    rng: np.random.Generator):
30	    raise NotImplementedError("implement train_val_split")
31	
32	
33	def iter_batches(X: np.ndarray, y: np.ndarray, batch_size: int,
34	           
…[truncated 814 chars]

/app/submission/train.py

contents
1	"""Adversarial-training loop for the small CNN, using the from-scratch numpy framework
2	(IMPLEMENT THIS).
3	
4	Standard (clean) training reaches ~99% CLEAN accuracy but ~chance ROBUST accuracy -- it is broken
5	by the verifier's STRONG multi-restart L-inf PGD attack. WEAK robust training is not enough either:
6	single-step (FGSM) adversarial training suffers "catastrophic overfitting" and is shattered by the
7	multi-step / multi-restart eval attack, and adversarial training at a SMALLER perturbation budget
8	than the eval budget leaves the model fragile exactly where it is attacked. The effective recipe is
9	full multi-step PGD ADVERSARIAL TRAINING (Madry et al. 2018) with the perturbation budget MATCHED
10	to the (larger) eval budget:
11	
12	  * on every minibatch, craft an inner k-step L-inf PGD adversarial batch against the CURRENT model
13	    (attack.pgd_attack), at the eps the eval uses, then take the AdamW step on advtrain.pgd_at_loss
14	    (cross-entropy on the adversarial batch);
15	  * train long enough for robustness to converge (a few epochs is not enough at this eps);
16	  * stability details that materially raise the achieved robust accuracy and make it reproducible:
17	    (a) exclude biases (1-D params) from weight decay (AdamW no_decay_ndim=1); (b) clip the global
18	    gradient norm (the adversarial loss surface is sharp); (c) keep the BEST-by-robust-accuracy
19	    checkpoint, evaluated each epoch with the model's own multi-step PGD on a held-BACK slic
…[truncated 2473 chars]
Now let me look at the run_checks.py to understand exactly what's tested and the expected interfaces, especially around `detach`/stop-gradient.

/app/run_checks.py

contents
<system-reminder>[Truncated: PARTIAL view , showing lines 1-868 of 1188 total (29062 tokens, cap 25000). Call Read with offset=869 limit=868 for the next page, or Grep to find a specific section. Do NOT answer from this page alone if the answer may be further in the file.]</system-reminder>

1	#!/usr/bin/env python3
2	"""PUBLIC component check runner for the from-scratch numpy framework + the adversarial machinery.
3	
4	Run this AS OFTEN AS YOU LIKE while you implement to get a per-check progress signal:
5	
6	    python3 /app/run_checks.py                       # check the framework in /app/submission
7	    python3 /app/run_checks.py --submission /some/dir
8	    python3 /app/run_checks.py --only attack         # focus a single milestone
9	
10	It imports YOUR modules from /app/submission (autograd.py / nn.py / optim.py / data.py / attack.py
11	/ advtrain.py), exactly as the grader does, and runs a PUBLIC portion of the component conformance
12	suite, printing a clear per-check report. Each FAIL line names the exact op / layer / optimizer /
13	attack / adversarial-training property that is wrong.
14	
15	HOW THIS RELATES TO YOUR GRADE
16	------------------------------
17	This runner is a DEBUGGING AID, not the grader. It checks YOUR framework against self-consistent
18	references it computes on its OWN:
19	  * autograd_grads : central FINITE-DIFFERENCE of YOUR forward vs YOUR analytic backward (every op,
20	                     incl. the convolution input-gradient, the pools, an
…[truncated 44212 chars]
Let me read the rest.

/app/run_checks.py

contents
869	    def dlr_loss_grad():
870	        rng = np.random.default_rng(sb + 60)
871	        x0 = rng.standard_normal((5, 4)); y = rng.integers(0, 4, size=5)
872	        lt = ag.Tensor(x0.copy(), requires_grad=True)
873	        atk.dlr_loss(lt, y).backward()
874	        gnum = _num_grad_input(lambda xv: np.array(float(atk.dlr_loss(ag.Tensor(xv), y).data)), x0.copy())
875	        return _max_abs(lt.grad, gnum) < TOL_GRAD, f"max_abs={_max_abs(lt.grad, gnum):.2e}"
876	
877	    def dlr_input_grad_fd():
878	        m = _model(61)
879	        x0 = np.random.default_rng(sb + 62).standard_normal((3, 1, 8, 8)); y = np.array([0, 1, 2])
880	        lf = lambda lg, t: atk.dlr_loss(lg, t)
881	        gan = np.asarray(atk.loss_input_grad(m, x0, y, lf), np.float64)
882	        gnum = _num_grad_input(lambda xv: np.array(float(lf(m(ag.Tensor(xv)), y).data)), x0.copy())
883	        return _max_abs(gan, gnum) < TOL_GRAD, f"max_abs={_max_abs(gan, gnum):.2e}"
884	
885	    def bim_stronger():
886	        m = _model(67)
887	        x = np.clip(np.random.default_rng(sb + 68).random((8, 1, 8, 8)), 0, 1); y = np.array([0, 1, 2, 3, 0, 1, 2, 3]); eps = 0.12
888	        xf = atk.fgsm(m, x, y, eps); xb = atk.bim(m, x, y, eps, 15, 0.025)
889	        lf = float(ag.cross_entropy(m(xf), y).data); lb = float(ag.cross_entropy(m(xb), y).data)
890	        return lb >= lf - 1e-6, f"fgsm={lf:.3f} bim={lb:.3f}"
891	
892	    def restarts_worst_case():
893	        m = _model(69)
894	        x = np.clip(np.random.default_
…[truncated 15653 chars]
Now I have a complete understanding. The key insight: detach = `Tensor(data.copy())`. Let me write `autograd.py`.
write · /app/submission/autograd.py
"""Reverse-mode automatic differentiation over numpy arrays."""
from __future__ import annotations

import math
from typing import Callable, Iterable, List, Optional

import numpy as np

_ERF = np.vectorize(math.erf)
_SQRT2 = math.sqrt(2.0)
_SQRT2PI = math.sqrt(2.0 * math.pi)


def _as_f64(x) -> np.ndarray:
    return np.asarray(x, dtype=np.float64)


def _unbroadcast(grad: np.ndarray, shape: tuple) -> np.ndarray:
    grad = np.asarray(grad, dtype=np.float64)
    while grad.ndim > len(shape):
        grad = grad.sum(axis=0)
    for i, s in enumerate(shape):
        if s == 1 and grad.shape[i] != 1:
            grad = grad.sum(axis=i, keepdims=True)
    return grad


def _unreduce(g, shape, axis, keepdims):
    g = np.asarray(g, dtype=np.float64)
    if axis is None:
        return np.broadcast_to(g, shape).copy()
    ax = axis if isinstance(axis, tuple) else (axis,)
    ax = tuple(a % len(shape) for a in ax)
    if not keepdims:
        g = np.expand_dims(g, ax)
    return np.broadcast_to(g, shape).copy()


def _count(shape, axis):
    if axis is None:
        n = 1
        for s in shape:
            n *= s
        return n
    ax = axis if isinstance(axis, tuple) else (axis,)
    n = 1
    for a in ax:
        n *= shape[a]
    return n


class Tensor:
    __slots__ = ("data", "grad", "requires_grad", "_backward", "_parents")

    def __init__(self, data, requires_grad: bool = False, _parents: Iterable["Tensor"] = ()):
        self.data: np.ndarray = _as_f64(data)
        s
…[truncated 27835 chars]

contents
The file /app/submission/autograd.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now `nn.py` forwards:

/app/submission/nn.py

− removed
    def forward(self, x: Tensor) -> Tensor:
        """ag.conv2d(x, weight, bias, pad)."""
        raise NotImplementedError("implement Conv2d.forward")
+ added
    def forward(self, x: Tensor) -> Tensor:
        """ag.conv2d(x, weight, bias, pad)."""
        return ag.conv2d(x, self.weight, self.bias, self.pad)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.maxpool2d(x, k)."""
        raise NotImplementedError("implement MaxPool2d.forward")
+ added
        """ag.maxpool2d(x, k)."""
        return ag.maxpool2d(x, self.k)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.avgpool2d(x, k)."""
        raise NotImplementedError("implement AvgPool2d.forward")
+ added
        """ag.avgpool2d(x, k)."""
        return ag.avgpool2d(x, self.k)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.matmul(x, weight) + bias."""
        raise NotImplementedError("implement Linear.forward")
+ added
        """ag.matmul(x, weight) + bias."""
        return ag.add(ag.matmul(x, self.weight), self.bias)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.layernorm(x, weight, bias, eps)."""
        raise NotImplementedError("implement LayerNorm.forward")
+ added
        """ag.layernorm(x, weight, bias, eps)."""
        return ag.layernorm(x, self.weight, self.bias, self.eps)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.batchnorm(x, weight, bias, eps)."""
        raise NotImplementedError("implement BatchNorm1d.forward")
+ added
        """ag.batchnorm(x, weight, bias, eps)."""
        return ag.batchnorm(x, self.weight, self.bias, self.eps)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """linear -> relu (between layers) -> ... -> linear (no final activation)."""
        raise NotImplementedError("implement MLP.forward")
+ added
        """linear -> relu (between layers) -> ... -> linear (no final activation)."""
        for i, lin in enumerate(self.layers):
            x = lin(x)
            if i < len(self.layers) - 1:
                x = ag.relu(x)
        return x

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """for each conv: pool(relu(conv(x))); then flatten -> relu(fc1) -> fc2."""
        raise NotImplementedError("implement ConvNet.forward")
+ added
        """for each conv: pool(relu(conv(x))); then flatten -> relu(fc1) -> fc2."""
        x = ag._ensure(x)
        for conv in self.convs:
            x = self.pool(ag.relu(conv(x)))
        n = x.shape[0]
        x = ag.reshape(x, (n, -1))
        x = ag.relu(self.fc1(x))
        return self.fc2(x)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.groupnorm(x, weight, bias, num_groups, eps)."""
        raise NotImplementedError("implement GroupNorm.forward")
+ added
        """ag.groupnorm(x, weight, bias, num_groups, eps)."""
        return ag.groupnorm(x, self.weight, self.bias, self.num_groups, self.eps)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """ag.rmsnorm(x, weight, eps)."""
        raise NotImplementedError("implement RMSNorm.forward")
+ added
        """ag.rmsnorm(x, weight, eps)."""
        return ag.rmsnorm(x, self.weight, self.eps)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now the recurrent cells:

/app/submission/nn.py

− removed
        """h' = tanh(x @ weight_ih^T + bias_ih + h @ weight_hh^T + bias_hh)."""
        raise NotImplementedError("implement RNNCell.forward")
+ added
        """h' = tanh(x @ weight_ih^T + bias_ih + h @ weight_hh^T + bias_hh)."""
        wi = ag.transpose(self.weight_ih)
        wh = ag.transpose(self.weight_hh)
        pre = ag.add(ag.add(ag.matmul(x, wi), self.bias_ih),
                     ag.add(ag.matmul(h, wh), self.bias_hh))
        return ag.tanh(pre)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """the GRU update above (slice the 3 gates out of the (N,3H) pre-activations)."""
        raise NotImplementedError("implement GRUCell.forward")
+ added
        """the GRU update above (slice the 3 gates out of the (N,3H) pre-activations)."""
        H = self.hidden_size
        gi = ag.add(ag.matmul(x, ag.transpose(self.weight_ih)), self.bias_ih)
        gh = ag.add(ag.matmul(h, ag.transpose(self.weight_hh)), self.bias_hh)
        i_r = gi[:, 0:H]; i_z = gi[:, H:2 * H]; i_n = gi[:, 2 * H:3 * H]
        h_r = gh[:, 0:H]; h_z = gh[:, H:2 * H]; h_n = gh[:, 2 * H:3 * H]
        r = ag.sigmoid(ag.add(i_r, h_r))
        z = ag.sigmoid(ag.add(i_z, h_z))
        n = ag.tanh(ag.add(i_n, ag.mul(r, h_n)))
        one_minus_z = ag.sub(1.0, z)
        return ag.add(ag.mul(one_minus_z, n), ag.mul(z, h))

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """the LSTM update above; return (h', c')."""
        raise NotImplementedError("implement LSTMCell.forward")
+ added
        """the LSTM update above; return (h', c')."""
        H = self.hidden_size
        g = ag.add(ag.add(ag.matmul(x, ag.transpose(self.weight_ih)), self.bias_ih),
                   ag.add(ag.matmul(h, ag.transpose(self.weight_hh)), self.bias_hh))
        i = ag.sigmoid(g[:, 0:H])
        f = ag.sigmoid(g[:, H:2 * H])
        gg = ag.tanh(g[:, 2 * H:3 * H])
        o = ag.sigmoid(g[:, 3 * H:4 * H])
        c2 = ag.add(ag.mul(f, c), ag.mul(i, gg))
        h2 = ag.mul(o, ag.tanh(c2))
        return h2, c2

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """h = pool(relu(conv1(x))); res = conv2b(relu(conv2a(h))); h = relu(h + res); flatten -> fc."""
        raise NotImplementedError("implement SmallResCNN.forward")
+ added
        """h = pool(relu(conv1(x))); res = conv2b(relu(conv2a(h))); h = relu(h + res); flatten -> fc."""
        x = ag._ensure(x)
        h = self.pool(ag.relu(self.conv1(x)))
        res = self.conv2b(ag.relu(self.conv2a(h)))
        h = ag.relu(ag.add(h, res))
        n = h.shape[0]
        h = ag.reshape(h, (n, -1))
        return self.fc(h)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/nn.py

− removed
        """conv1 -> relu -> pool -> conv2 -> relu -> pool -> flatten -> fc1 -> relu -> fc2."""
        raise NotImplementedError("implement SmallCNN.forward")
+ added
        """conv1 -> relu -> pool -> conv2 -> relu -> pool -> flatten -> fc1 -> relu -> fc2."""
        x = ag._ensure(x)
        x = self.pool(ag.relu(self.conv1(x)))
        x = self.pool(ag.relu(self.conv2(x)))
        n = x.shape[0]
        x = ag.reshape(x, (n, -1))
        x = ag.relu(self.fc1(x))
        return self.fc2(x)

contents
The file /app/submission/nn.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now data.py:

/app/submission/data.py

− removed
def load_npz(path: str) -> Tuple[np.ndarray, np.ndarray]:
    raise NotImplementedError("implement load_npz")


def train_val_split(X: np.ndarray, y: np.ndarray, val_frac: float,
                    rng: np.random.Generator):
    raise NotImplementedError("implement train_val_split")


def iter_batches(X: np.ndarray, y: np.ndarray, batch_size: int,
                 rng: np.random.Generator) -> Iterator[Tuple[np.ndarray, np.ndarray]]:
    raise NotImplementedError("implement iter_batches")


def get_batch(X: np.ndarray, y: np.ndarray, batch_size: int,
              rng: np.random.Generator) -> Tuple[np.ndarray, np.ndarray]:
    """A single random minibatch (without replacement if possible). Shape-preserving."""
    raise NotImplementedError("implement get_batch")


def to_onehot(y: np.ndarray, n_classes: int) -> np.ndarray:
    """(N, n_classes) one-hot float matrix from integer labels y."""
    raise NotImplementedError("implement to_onehot")


def clip01(X: np.ndarray) -> np.ndarray:
    """Clamp X into the [0,1] pixel domain (the valid attack range)."""
    raise NotImplementedError("implement clip01")
+ added
def load_npz(path: str) -> Tuple[np.ndarray, np.ndarray]:
    d = np.load(path)
    X = np.asarray(d["X"], dtype=np.float64)
    y = np.asarray(d["y"], dtype=np.int64)
    return X, y


def train_val_split(X: np.ndarray, y: np.ndarray, val_frac: float,
                    rng: np.random.Generator):
    n = X.shape[0]
    perm = rng.permutation(n)
    nval = int(round(n * val_frac))
    val_idx = perm[:nval]
    tr_idx = perm[nval:]
    return (X[tr_idx], y[tr_idx]), (X[val_idx], y[val_idx])


def iter_batches(X: np.ndarray, y: np.ndarray, batch_size: int,
                 rng: np.random.Generator) -> Iterator[Tuple[np.ndarray, np.ndarray]]:
    n = X.shape[0]
    perm = rng.permutation(n)
    for s in range(0, n, batch_size):
        idx = perm[s:s + batch_size]
        yield X[idx], y[idx]


def get_batch(X: np.ndarray, y: np.ndarray, batch_size: int,
              rng: np.random.Generator) -> Tuple[np.ndarray, np.ndarray]:
    """A single random minibatch (without replacement if possible). Shape-preserving."""
    n = X.shape[0]
    replace = batch_size > n
    idx = rng.choice(n, size=batch_size, replace=replace)
    return X[idx], y[idx]


def to_onehot(y: np.ndarray, n_classes: int) -> np.ndarray:
    """(N, n_classes) one-hot float matrix from integer labels y."""
    y = np.asarray(y).astype(int)
    oh = np.zeros((y.shape[0], n_classes), dtype=np.float64)
    oh[np.arange(y.shape[0]), y] = 1.0
    return oh


def clip01(X: np.ndarray) -> np.ndarray:
    """Clamp X int
…[truncated 85 chars]

contents
The file /app/submission/data.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now let me run the autograd, nn, and data checks before continuing:
shell
python3 run_checks.py --only autograd_grads 2>&1 | tail -40
output
grad/prod_axis                           OK    (max_abs=5.65e-10)
  grad/cumsum_ax1                          OK    (max_abs=3.79e-11)
  grad/logsumexp_ax1                       OK    (max_abs=4.93e-11)
  grad/pad2d                               OK    (max_abs=5.10e-11)
  grad/groupnorm_x                         OK  
  grad/rmsnorm_x                           OK  
  grad/layernorm_x                         OK  
  grad/batchnorm_x                         OK  
  grad/embedding                           OK  
  grad/mse_loss                            OK  
  grad/cross_entropy                       OK  
  grad/kl_div_q                            OK  
  grad/kl_div_p                            OK  
  grad/conv2d_input                        OK    (max_abs=1.33e-09)
  grad/conv2d_weight                       OK    (max_abs=3.61e-09)
  grad/conv2d_bias                         OK  
  grad/conv2d_pad0_input                   OK    (max_abs=8.78e-10)
  grad/maxpool2d                           OK  
  grad/avgpool2d                           OK  
  grad/nn.Conv2d_x                         OK  
  grad/nn.Linear_x                         OK  
  grad/nn.LayerNorm_x                      OK  
  grad/nn.BatchNorm1d_x                    OK  
  grad/cnn_grad_fc2.bias                   OK    (max_abs=1.71e-11)
  grad/cnn_grad_conv1.weight               OK    (max_abs=2.36e-11)
  grad/cnn_grad_conv2.weight               OK    (max_abs=2.75e-11)
  grad/cnn_grad_fc1.weight                 OK    (ma
…[truncated 815 chars]
All autograd grads pass. Now nn_forward and data:
shell
python3 run_checks.py --only nn_forward 2>&1 | tail -30 && echo "===DATA===" && python3 run_checks.py --only data 2>&1 | tail -8
output
[nn_forward]  22/22
  fwd/relu_def                             OK  
  fwd/leaky_relu_def                       OK  
  fwd/sigmoid_def                          OK  
  fwd/tanh_def                             OK  
  fwd/gelu_erf_def                         OK  
  fwd/softplus_def                         OK  
  fwd/silu_def                             OK  
  fwd/elu_def                              OK  
  fwd/logsumexp_def                        OK  
  fwd/softmax_rows_sum_1                   OK  
  fwd/cross_entropy_value                  OK  
  fwd/kl_self_zero                         OK    (KL(p||p)==0)
  fwd/layernorm_row_stats                  OK  
  fwd/groupnorm_stats                      OK  
  fwd/rmsnorm_def                          OK  
  fwd/conv2d_arithmetic                    OK  
  fwd/maxpool2d_def                        OK  
  fwd/avgpool2d_def                        OK  
  fwd/Linear_def                           OK  
  fwd/SmallCNN_shape                       OK    (shape=(4, 5))
  fwd/SmallResCNN_shape                    OK    (shape=(4, 3))
  fwd/SmallCNN_state_dict_roundtrip        OK    (state_dict round-trips)

------------------------------------------------------------------------
nn_forward 22/22
TOTAL  22/22 public checks passing
All public checks pass. Now make sure model.npz clears the held-out ROBUST-accuracy threshold; the grader re-checks with DIFFERENT seeds/shapes + its OWN strong PGD.
===DATA===
  data/get_batch_shape                     OK   
…[truncated 409 chars]
Now optim.py:

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement SGD.step")
+ added
    def step(self):
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            v = self.momentum * self._v[i] + g
            self._v[i] = v
            step = (g + self.momentum * v) if self.nesterov else v
            p.data -= self.lr * step

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement Adagrad.step")
+ added
    def step(self):
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._s[i] += g * g
            p.data -= self.lr * g / (np.sqrt(self._s[i]) + self.eps)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement RMSprop.step")
+ added
    def step(self):
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._s[i] = self.alpha * self._s[i] + (1 - self.alpha) * (g * g)
            p.data -= self.lr * g / (np.sqrt(self._s[i]) + self.eps)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement Adam.step")
+ added
    def step(self):
        self.t += 1
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._m[i] = self.b1 * self._m[i] + (1 - self.b1) * g
            self._v[i] = self.b2 * self._v[i] + (1 - self.b2) * (g * g)
            mhat = self._m[i] / (1 - self.b1 ** self.t)
            vhat = self._v[i] / (1 - self.b2 ** self.t)
            p.data -= self.lr * mhat / (np.sqrt(vhat) + self.eps)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement AdamW.step")
+ added
    def step(self):
        self.t += 1
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad
            self._m[i] = self.b1 * self._m[i] + (1 - self.b1) * g
            self._v[i] = self.b2 * self._v[i] + (1 - self.b2) * (g * g)
            mhat = self._m[i] / (1 - self.b1 ** self.t)
            vhat = self._v[i] / (1 - self.b2 ** self.t)
            wd_eff = 0.0 if p.data.ndim <= self.no_decay_ndim else self.weight_decay
            p.data -= self.lr * (mhat / (np.sqrt(vhat) + self.eps) + wd_eff * p.data)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement Adamax.step")
+ added
    def step(self):
        self.t += 1
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._m[i] = self.b1 * self._m[i] + (1 - self.b1) * g
            self._u[i] = np.maximum(self.b2 * self._u[i], np.abs(g))
            p.data -= (self.lr / (1 - self.b1 ** self.t)) * self._m[i] / (self._u[i] + self.eps)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement NAdam.step")
+ added
    def step(self):
        self.t += 1
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._m[i] = self.b1 * self._m[i] + (1 - self.b1) * g
            self._v[i] = self.b2 * self._v[i] + (1 - self.b2) * (g * g)
            mhat = self._m[i] / (1 - self.b1 ** self.t)
            vhat = self._v[i] / (1 - self.b2 ** self.t)
            mnes = self.b1 * mhat + (1 - self.b1) * g / (1 - self.b1 ** self.t)
            p.data -= self.lr * mnes / (np.sqrt(vhat) + self.eps)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement Lion.step")
+ added
    def step(self):
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad
            c = np.sign(self.b1 * self._m[i] + (1 - self.b1) * g)
            p.data -= self.lr * (c + self.weight_decay * p.data)
            self._m[i] = self.b2 * self._m[i] + (1 - self.b2) * g

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
    def step(self):
        raise NotImplementedError("implement Adadelta.step")
+ added
    def step(self):
        for i, p in enumerate(self.params):
            if p.grad is None:
                continue
            g = p.grad + self.weight_decay * p.data
            self._s[i] = self.rho * self._s[i] + (1 - self.rho) * (g * g)
            delta = np.sqrt(self._d[i] + self.eps) / np.sqrt(self._s[i] + self.eps) * g
            p.data -= self.lr * delta
            self._d[i] = self.rho * self._d[i] + (1 - self.rho) * (delta * delta)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now the clippers and schedulers:

/app/submission/optim.py

− removed
    scale every grad by max_norm/(total+1e-6)."""
    raise NotImplementedError("implement clip_grad_norm")
+ added
    scale every grad by max_norm/(total+1e-6)."""
    total = 0.0
    for p in params:
        if p.grad is not None:
            total += float((p.grad ** 2).sum())
    total = math.sqrt(total)
    if total > max_norm:
        scale = max_norm / (total + 1e-6)
        for p in params:
            if p.grad is not None:
                p.grad = p.grad * scale
    return total

contents
<tool_use_error>String to replace not found in file.
String:     scale every grad by max_norm/(total+1e-6)."""
    raise NotImplementedError("implement clip_grad_norm")</tool_use_error>

/app/submission/optim.py

contents
186	        for i, p in enumerate(self.params):
187	            if p.grad is None:
188	                continue
189	            g = p.grad + self.weight_decay * p.data
190	            self._m[i] = self.b1 * self._m[i] + (1 - self.b1) * g
191	            self._v[i] = self.b2 * self._v[i] + (1 - self.b2) * (g * g)
192	            mhat = self._m[i] / (1 - self.b1 ** self.t)
193	            vhat = self._v[i] / (1 - self.b2 ** self.t)
194	            mnes = self.b1 * mhat + (1 - self.b1) * g / (1 - self.b1 ** self.t)
195	            p.data -= self.lr * mnes / (np.sqrt(vhat) + self.eps)
196	
197

/app/submission/optim.py

contents
218	class Adadelta(Optimizer):
219	    """Adadelta (Zeiler 2012), coupled wd (lr is a multiplier, default 1.0):
220	        g = grad + wd*param; s = rho*s + (1-rho)*g*g;
221	        delta = sqrt(d + eps)/sqrt(s + eps) * g; param -= lr*delta; d = rho*d + (1-rho)*delta*delta."""
222	
223	    def __init__(self, params, lr=1.0, rho=0.9, eps=1e-6, weight_decay=0.0):
224	        super().__init__(params)
225	        self.lr, self.rho, self.eps, self.weight_decay = lr, rho, eps, weight_decay
226	        self._s = [np.zeros_like(p.data) for p in self.params]
227	        self._d = [np.zeros_like(p.data) for p in self.params]
228	
229	    def step(self):
230	        for i, p in enumerate(self.params):
231	            if p.grad is None:
232	                continue
233	            g = p.grad + self.weight_decay * p.data
234	            self._s[i] = self.rho * self._s[i] + (1 - self.rho) * (g * g)
235	            delta = np.sqrt(self._d[i] + self.eps) / np.sqrt(self._s[i] + self.eps) * g
236	            p.data -= self.lr * delta
237	            self._d[i] = self.rho * self._d[i] + (1 - self.rho) * (delta * delta)
238	
239	
240	# ===================================================================== grad clipping
241	def clip_grad_norm(params: List[Tensor], max_norm: float) -> float:
242	    """Global L2 gradient-norm clipping. Return the pre-clip total norm. If total > max_norm, scale
243	    every grad by max_norm/(total+1e-6)."""
244	    raise NotImplementedError("implement clip_grad_nor
…[truncated 2092 chars]

/app/submission/optim.py

− removed
    every grad by max_norm/(total+1e-6)."""
    raise NotImplementedError("implement clip_grad_norm")


def clip_grad_value(params: List[Tensor], clip_value: float) -> None:
    """Element-wise gradient clipping: clamp every grad to [-clip_value, clip_value]."""
    raise NotImplementedError("implement clip_grad_value")
+ added
    every grad by max_norm/(total+1e-6)."""
    total = 0.0
    for p in params:
        if p.grad is not None:
            total += float((p.grad ** 2).sum())
    total = math.sqrt(total)
    if total > max_norm:
        scale = max_norm / (total + 1e-6)
        for p in params:
            if p.grad is not None:
                p.grad = p.grad * scale
    return total


def clip_grad_value(params: List[Tensor], clip_value: float) -> None:
    """Element-wise gradient clipping: clamp every grad to [-clip_value, clip_value]."""
    for p in params:
        if p.grad is not None:
            p.grad = np.clip(p.grad, -clip_value, clip_value)

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/optim.py

− removed
        else: min_lr + 0.5*(base_lr-min_lr)*(1+cos(pi*progress)), progress=clip((step-warmup)/(total-warmup),0,1)."""
    raise NotImplementedError("implement cosine_lr")


def warmup_lr(step: int, base_lr: float, warmup: int) -> float:
    """Linear warmup to base_lr over warmup steps, flat after: base_lr*(step+1)/warmup if step<warmup else base_lr."""
    raise NotImplementedError("implement warmup_lr")


def step_lr(step: int, base_lr: float, step_size: int, gamma: float = 0.1) -> float:
    """Step decay: base_lr * gamma ** (step // step_size)."""
    raise NotImplementedError("implement step_lr")


def exponential_lr(step: int, base_lr: float, gamma: float = 0.95) -> float:
    """Exponential decay: base_lr * gamma ** step."""
    raise NotImplementedError("implement exponential_lr")


def polynomial_lr(step: int, total: int, base_lr: float, power: float = 2.0,
                  min_lr: float = 0.0) -> float:
    """Polynomial decay to min_lr over total steps: progress=clip(step/total,0,1);
    lr = (base_lr-min_lr)*(1-progress)**power + min_lr."""
    raise NotImplementedError("implement polynomial_lr")


def linear_lr(step: int, total: int, base_lr: float, min_lr: float = 0.0) -> float:
    """Linear decay base_lr->min_lr over total steps (flat after): progress=clip(step/total,0,1);
    lr = base_lr + (min_lr-base_lr)*progress."""
    raise NotImplementedError("implement linear_lr")
+ added
        else: min_lr + 0.5*(base_lr-min_lr)*(1+cos(pi*progress)), progress=clip((step-warmup)/(total-warmup),0,1)."""
    if warmup > 0 and step < warmup:
        return base_lr * (step + 1) / warmup
    prog = min(1.0, max(0.0, (step - warmup) / max(1, total - warmup)))
    return min_lr + 0.5 * (base_lr - min_lr) * (1 + math.cos(math.pi * prog))


def warmup_lr(step: int, base_lr: float, warmup: int) -> float:
    """Linear warmup to base_lr over warmup steps, flat after: base_lr*(step+1)/warmup if step<warmup else base_lr."""
    if step < warmup:
        return base_lr * (step + 1) / warmup
    return base_lr


def step_lr(step: int, base_lr: float, step_size: int, gamma: float = 0.1) -> float:
    """Step decay: base_lr * gamma ** (step // step_size)."""
    return base_lr * (gamma ** (step // step_size))


def exponential_lr(step: int, base_lr: float, gamma: float = 0.95) -> float:
    """Exponential decay: base_lr * gamma ** step."""
    return base_lr * (gamma ** step)


def polynomial_lr(step: int, total: int, base_lr: float, power: float = 2.0,
                  min_lr: float = 0.0) -> float:
    """Polynomial decay to min_lr over total steps: progress=clip(step/total,0,1);
    lr = (base_lr-min_lr)*(1-progress)**power + min_lr."""
    prog = min(1.0, max(0.0, step / total))
    return (base_lr - min_lr) * ((1.0 - prog) ** power) + min_lr


def linear_lr(step: int, total: int, base_lr: float, min_lr: float = 0.0) -> float:
    """Linear decay base_lr->min_lr over to
…[truncated 194 chars]

contents
The file /app/submission/optim.py has been updated successfully. (file state is current in your context , no need to Read it back)
shell
python3 run_checks.py --only optim 2>&1 | tail -35
output
[optim]  20/20
  optim/SGD_1step                          OK    (max_abs=0.0e+00)
  optim/SGD_momentum_5step                 OK    (max_abs=0.0e+00)
  optim/SGD_nesterov_5step                 OK    (max_abs=0.0e+00)
  optim/Adagrad_5step                      OK    (max_abs=0.0e+00)
  optim/RMSprop_5step                      OK    (max_abs=0.0e+00)
  optim/Adam_10step_wd                     OK    (max_abs=0.0e+00)
  optim/AdamW_10step_wd                    OK    (max_abs=0.0e+00)
  optim/Adamax_8step                       OK    (max_abs=0.0e+00)
  optim/NAdam_8step                        OK    (max_abs=0.0e+00)
  optim/Lion_8step_wd                      OK    (max_abs=0.0e+00)
  optim/Adadelta_8step                     OK    (max_abs=0.0e+00)
  optim/clip_grad_norm_clips               OK    (max_abs=0.0e+00)
  optim/clip_grad_norm_noop                OK    (max_abs=0.0e+00)
  optim/clip_grad_value                    OK    (max_abs=0.0e+00)
  optim/sched_cosine_lr                    OK    (match)
  optim/sched_warmup_lr                    OK    (match)
  optim/sched_step_lr                      OK    (match)
  optim/sched_exponential_lr               OK    (match)
  optim/sched_polynomial_lr                OK    (match)
  optim/sched_linear_lr                    OK    (match)

------------------------------------------------------------------------
optim 20/20
TOTAL  20/20 public checks passing
All public checks pass. Now make sure model.npz clears the held-out ROBUST-accuracy 
…[truncated 81 chars]
Now attack.py. Let me implement all attacks:

/app/submission/attack.py

− removed
    in a requires_grad=True Tensor, forward, compute loss_fn, backprop, return xt.grad."""
    raise NotImplementedError("implement loss_input_grad")


def input_grad(model, x: np.ndarray, y: np.ndarray) -> np.ndarray:
    """d/dx of mean CROSS-ENTROPY of model(x) vs y (the standard attack gradient)."""
    raise NotImplementedError("implement input_grad")
+ added
    in a requires_grad=True Tensor, forward, compute loss_fn, backprop, return xt.grad."""
    xt = Tensor(np.asarray(x, dtype=np.float64), requires_grad=True)
    logits = model(xt)
    loss = loss_fn(logits, y)
    loss.backward()
    return np.asarray(xt.grad, dtype=np.float64)


def input_grad(model, x: np.ndarray, y: np.ndarray) -> np.ndarray:
    """d/dx of mean CROSS-ENTROPY of model(x) vs y (the standard attack gradient)."""
    return loss_input_grad(model, x, y, lambda lg, t: ag.cross_entropy(lg, t))

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    Build it with autograd ops so the input-gradient flows; returns a scalar Tensor."""
    raise NotImplementedError("implement cw_margin_loss")
+ added
    Build it with autograd ops so the input-gradient flows; returns a scalar Tensor."""
    logits = ag._ensure(logits)
    N, C = logits.shape
    y = np.asarray(y).astype(int)
    idx = (np.arange(N), y)
    onehot = np.zeros((N, C), dtype=bool)
    onehot[idx] = True
    z_y = ag.getitem(logits, idx)
    masked = ag.where(onehot, Tensor(np.full((N, C), -1e30)), logits)
    other_max = ag.max(masked, axis=-1)
    margin = ag.sub(z_y, other_max)
    per = ag.maximum(ag.mul(margin, -1.0), -float(kappa))
    return ag.mean(per)

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    it differentiates exactly and the input-gradient flows; returns a scalar Tensor."""
    raise NotImplementedError("implement dlr_loss")
+ added
    it differentiates exactly and the input-gradient flows; returns a scalar Tensor."""
    logits = ag._ensure(logits)
    N, C = logits.shape
    y = np.asarray(y).astype(int)
    idx = (np.arange(N), y)
    onehot = np.zeros((N, C), dtype=bool)
    onehot[idx] = True
    z_y = ag.getitem(logits, idx)
    masked = ag.where(onehot, Tensor(np.full((N, C), -1e30)), logits)
    other_max = ag.max(masked, axis=-1)
    max_all = ag.max(logits, axis=-1)
    mean_all = ag.mean(logits, axis=-1)
    num = ag.sub(z_y, other_max)
    denom = ag.add(ag.sub(max_all, mean_all), float(eps))
    dlr = ag.mul(ag.div(num, denom), -1.0)
    return ag.mean(dlr)

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)
Now the projections and the attack algorithms:

/app/submission/attack.py

− removed
    """Project x_adv into the L-inf eps-ball around x, then into [lo,hi]."""
    raise NotImplementedError("implement project_linf")
+ added
    """Project x_adv into the L-inf eps-ball around x, then into [lo,hi]."""
    xa = np.clip(x_adv, x - eps, x + eps)
    return np.clip(xa, lo, hi)

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """Project x_adv so the PER-EXAMPLE L-2 norm of (x_adv - x) is <= eps, then clip to [lo,hi]."""
    raise NotImplementedError("implement project_l2")
+ added
    """Project x_adv so the PER-EXAMPLE L-2 norm of (x_adv - x) is <= eps, then clip to [lo,hi]."""
    delta = x_adv - x
    N = delta.shape[0]
    flat = delta.reshape(N, -1)
    norm = np.linalg.norm(flat, axis=1, keepdims=True)
    factor = np.minimum(1.0, eps / (norm + 1e-12))
    flat = flat * factor
    xa = x + flat.reshape(delta.shape)
    return np.clip(xa, lo, hi)

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """One-step FGSM: clip(x + eps*sign(input_grad))."""
    raise NotImplementedError("implement fgsm")
+ added
    """One-step FGSM: clip(x + eps*sign(input_grad))."""
    g = input_grad(model, x, y)
    xadv = x + eps * np.sign(g)
    return np.clip(xadv, clip[0], clip[1])

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """Iterated FGSM with random start + L-inf projection (the standard PGD attack)."""
    raise NotImplementedError("implement pgd_attack")
+ added
    """Iterated FGSM with random start + L-inf projection (the standard PGD attack)."""
    lo, hi = clip
    x0 = x if x0 is None else x0
    if rng is None:
        xadv = x.copy()
    else:
        xadv = x + rng.uniform(-eps, eps, size=x.shape)
    xadv = project_linf(xadv, x0, eps, lo, hi)
    for _ in range(steps):
        g = input_grad(model, xadv, y)
        xadv = xadv + alpha * np.sign(g)
        xadv = project_linf(xadv, x0, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    project to the L-inf ball + box each step."""
    raise NotImplementedError("implement mi_fgsm")
+ added
    project to the L-inf ball + box each step."""
    lo, hi = clip
    N = x.shape[0]
    if rng is None:
        xadv = x.copy()
    else:
        xadv = project_linf(x + rng.uniform(-eps, eps, size=x.shape), x, eps, lo, hi)
    gmom = np.zeros_like(x)
    for _ in range(steps):
        g = input_grad(model, xadv, y)
        gnorm = np.sum(np.abs(g.reshape(N, -1)), axis=1).reshape([N] + [1] * (g.ndim - 1))
        gmom = mu * gmom + g / (gnorm + 1e-12)
        xadv = xadv + alpha * np.sign(gmom)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """Targeted PGD: DESCEND CE toward y_target (step on the NEGATIVE gradient sign); project each step."""
    raise NotImplementedError("implement targeted_pgd")
+ added
    """Targeted PGD: DESCEND CE toward y_target (step on the NEGATIVE gradient sign); project each step."""
    lo, hi = clip
    if rng is None:
        xadv = x.copy()
    else:
        xadv = project_linf(x + rng.uniform(-eps, eps, size=x.shape), x, eps, lo, hi)
    for _ in range(steps):
        g = input_grad(model, xadv, y_target)
        xadv = xadv - alpha * np.sign(g)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """PGD ascending the untargeted CW margin loss (cw_margin_loss); project to the ball + box each step."""
    raise NotImplementedError("implement cw_pgd")
+ added
    """PGD ascending the untargeted CW margin loss (cw_margin_loss); project to the ball + box each step."""
    lo, hi = clip
    lf = lambda lg, t: cw_margin_loss(lg, t, kappa)
    if rng is None:
        xadv = x.copy()
    else:
        xadv = project_linf(x + rng.uniform(-eps, eps, size=x.shape), x, eps, lo, hi)
    for _ in range(steps):
        g = loss_input_grad(model, xadv, y, lf)
        xadv = xadv + alpha * np.sign(g)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    into the L-2 eps-ball + pixel box each step."""
    raise NotImplementedError("implement pgd_l2")
+ added
    into the L-2 eps-ball + pixel box each step."""
    lo, hi = clip
    N = x.shape[0]
    if rng is None:
        xadv = x.copy()
    else:
        d = rng.standard_normal(x.shape)
        dn = np.linalg.norm(d.reshape(N, -1), axis=1, keepdims=True)
        d = d / (dn.reshape([N] + [1] * (x.ndim - 1)) + 1e-12) * eps * rng.random((N,) + (1,) * (x.ndim - 1))
        xadv = project_l2(x + d, x, eps, lo, hi)
    for _ in range(steps):
        g = input_grad(model, xadv, y)
        gn = np.linalg.norm(g.reshape(N, -1), axis=1).reshape([N] + [1] * (g.ndim - 1))
        xadv = xadv + alpha * g / (gn + 1e-12)
        xadv = project_l2(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    x_adv += alpha*sign(input_grad); project to the L-inf eps-ball + box."""
    raise NotImplementedError("implement bim")
+ added
    x_adv += alpha*sign(input_grad); project to the L-inf eps-ball + box."""
    lo, hi = clip
    xadv = x.copy()
    for _ in range(steps):
        g = input_grad(model, xadv, y)
        xadv = xadv + alpha * np.sign(g)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    size alpha; project to the eps-ball + box. Default alpha = eps/2."""
    raise NotImplementedError("implement rfgsm")
+ added
    size alpha; project to the eps-ball + box. Default alpha = eps/2."""
    lo, hi = clip
    if alpha is None:
        alpha = eps / 2.0
    if rng is None:
        rng = np.random.default_rng()
    xstart = x + (eps - alpha) * np.sign(rng.uniform(-1.0, 1.0, size=x.shape))
    xstart = np.clip(xstart, lo, hi)
    g = input_grad(model, xstart, y)
    xadv = xstart + alpha * np.sign(g)
    return project_linf(xadv, x, eps, lo, hi)

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    g_mom = mu*g_mom + grad/||grad||_1, step on sign(g_mom); project each step."""
    raise NotImplementedError("implement ni_fgsm")
+ added
    g_mom = mu*g_mom + grad/||grad||_1, step on sign(g_mom); project each step."""
    lo, hi = clip
    N = x.shape[0]
    if rng is None:
        xadv = x.copy()
    else:
        xadv = project_linf(x + rng.uniform(-eps, eps, size=x.shape), x, eps, lo, hi)
    gmom = np.zeros_like(x)
    for _ in range(steps):
        xnes = xadv + alpha * mu * gmom
        g = input_grad(model, xnes, y)
        gnorm = np.sum(np.abs(g.reshape(N, -1)), axis=1).reshape([N] + [1] * (g.ndim - 1))
        gmom = mu * gmom + g / (gnorm + 1e-12)
        xadv = xadv + alpha * np.sign(gmom)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    adversarial input with the HIGHEST per-example cross-entropy (worst case). Return that batch."""
    raise NotImplementedError("implement pgd_restarts")
+ added
    adversarial input with the HIGHEST per-example cross-entropy (worst case). Return that batch."""
    if rng is None:
        rng = np.random.default_rng()
    N = x.shape[0]
    best = None
    best_ce = np.full(N, -np.inf)
    for _ in range(restarts):
        xadv = pgd_attack(model, x, y, eps, steps, alpha, clip=clip, rng=rng)
        logits = model(Tensor(xadv))
        ce = np.asarray(ag.nll_per_sample(logits, y).data, dtype=np.float64)
        if best is None:
            best = xadv.copy()
        upd = ce > best_ce
        best[upd] = xadv[upd]
        best_ce[upd] = ce[upd]
    return best

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/attack.py

− removed
    """PGD ascending the DLR loss (dlr_loss) instead of CE; project to the L-inf ball + box each step."""
    raise NotImplementedError("implement dlr_pgd")
+ added
    """PGD ascending the DLR loss (dlr_loss) instead of CE; project to the L-inf ball + box each step."""
    lo, hi = clip
    lf = lambda lg, t: dlr_loss(lg, t)
    if rng is None:
        xadv = x.copy()
    else:
        xadv = project_linf(x + rng.uniform(-eps, eps, size=x.shape), x, eps, lo, hi)
    for _ in range(steps):
        g = loss_input_grad(model, xadv, y, lf)
        xadv = xadv + alpha * np.sign(g)
        xadv = project_linf(xadv, x, eps, lo, hi)
    return xadv

contents
The file /app/submission/attack.py has been updated successfully. (file state is current in your context , no need to Read it back)
shell
python3 run_checks.py --only attack 2>&1 | tail -25
output
[attack]  18/18
  attack/input_grad_fd                     OK    (max_abs=2.12e-11)
  attack/cw_loss_input_grad_fd             OK    (max_abs=2.41e-12)
  attack/dlr_loss_grad                     OK    (max_abs=1.04e-09)
  attack/dlr_loss_input_grad_fd            OK    (max_abs=2.81e-11)
  attack/fgsm_step                         OK  
  attack/pgd_projection                    OK  
  attack/mi_fgsm_projection                OK  
  attack/cw_pgd_projection                 OK  
  attack/pgd_l2_projection                 OK  
  attack/bim_projection                    OK  
  attack/rfgsm_projection                  OK  
  attack/ni_fgsm_projection                OK  
  attack/pgd_restarts_projection           OK  
  attack/dlr_pgd_projection                OK  
  attack/pgd_stronger_than_fgsm            OK    (fgsm=1.450 pgd=1.469)
  attack/bim_stronger_than_fgsm            OK    (fgsm=1.411 bim=1.423)
  attack/pgd_restarts_worst_case           OK    (single=1.521 restarts=1.525)
  attack/targeted_pgd_lowers_target_ce     OK    (1.388->1.333)

------------------------------------------------------------------------
attack 18/18
TOTAL  18/18 public checks passing
All public checks pass. Now make sure model.npz clears the held-out ROBUST-accuracy threshold; the grader re-checks with DIFFERENT seeds/shapes + its OWN strong PGD.
Now advtrain.py. The detach mechanism is `Tensor(t.data.copy())`:

/app/submission/advtrain.py

− removed
def pgd_at_loss(model, x_adv: np.ndarray, y: np.ndarray) -> Tensor:
    """Madry PGD-AT loss: cross-entropy on the adversarial batch (trains parameters)."""
    raise NotImplementedError("implement pgd_at_loss")


def trades_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.ndarray,
                beta: float = 6.0) -> Tuple[Tensor, Dict[str, float]]:
    """TRADES loss = CE(clean, y) + beta * KL(stopgrad(softmax(clean)) || softmax(adv))."""
    raise NotImplementedError("implement trades_loss")


def mart_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.ndarray,
              beta: float = 5.0) -> Tuple[Tensor, Dict[str, float]]:
    """MART loss (boosted CE on adv + misclassification-aware weighted KL with the clean target
    DETACHED); see the module docstring for the exact form."""
    raise NotImplementedError("implement mart_loss")


def alp_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.ndarray,
             lam: float = 0.5) -> Tuple[Tensor, Dict[str, float]]:
    """Adversarial Logit Pairing: 0.5*(CE(clean)+CE(adv)) + lam*mean||z_clean - z_adv||^2 (no detach)."""
    raise NotImplementedError("implement alp_loss")


def label_smoothed_ce(logits, y, eps_ls: float = 0.1, n_classes: int = None) -> Tensor:
    """CE against a label-smoothed target ((1-eps_ls)*onehot + eps_ls/C*uniform), via log_softmax."""
    raise NotImplementedError("implement label_smoothed_ce")


def robust_ce_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.nd
…[truncated 212 chars]
+ added
def _detach(t: Tensor) -> Tensor:
    return Tensor(t.data.copy())


def pgd_at_loss(model, x_adv: np.ndarray, y: np.ndarray) -> Tensor:
    """Madry PGD-AT loss: cross-entropy on the adversarial batch (trains parameters)."""
    return ag.cross_entropy(model(Tensor(np.asarray(x_adv, dtype=np.float64))), y)


def trades_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.ndarray,
                beta: float = 6.0) -> Tuple[Tensor, Dict[str, float]]:
    """TRADES loss = CE(clean, y) + beta * KL(stopgrad(softmax(clean)) || softmax(adv))."""
    cl = model(Tensor(np.asarray(x_clean, dtype=np.float64)))
    ad = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    ce = ag.cross_entropy(cl, y)
    tgt = _detach(cl)
    kl = ag.kl_div(tgt, ad)
    loss = ag.add(ce, ag.mul(kl, float(beta)))
    return loss, {"ce": float(ce.data), "kl": float(kl.data), "loss": float(loss.data)}


def mart_loss(model, x_clean: np.ndarray, x_adv: np.ndarray, y: np.ndarray,
              beta: float = 5.0) -> Tuple[Tensor, Dict[str, float]]:
    """MART loss (boosted CE on adv + misclassification-aware weighted KL with the clean target
    DETACHED); see the module docstring for the exact form."""
    cl = model(Tensor(np.asarray(x_clean, dtype=np.float64)))
    ad = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    y = np.asarray(y).astype(int)
    N, C = ad.shape
    idx = (np.arange(N), y)
    onehot = np.zeros((N, C), dtype=bool)
    onehot[idx] = True
    # boosted CE: CE(adv,y) - mea
…[truncated 2784 chars]

contents
The file /app/submission/advtrain.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/advtrain.py

− removed
    through the adversarial branch; the clean branch still trains via its CE term)."""
    raise NotImplementedError("implement clp_loss")
+ added
    through the adversarial branch; the clean branch still trains via its CE term)."""
    zc = model(Tensor(np.asarray(x_clean, dtype=np.float64)))
    za = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    ce = ag.mul(ag.add(ag.cross_entropy(zc, y), ag.cross_entropy(za, y)), 0.5)
    zc_det = _detach(zc)
    diff = ag.sub(zc_det, za)
    pair = ag.mean(ag.mul(diff, diff))
    loss = ag.add(ce, ag.mul(pair, float(lam)))
    return loss, {"ce": float(ce.data), "pair": float(pair.data), "loss": float(loss.data)}

contents
The file /app/submission/advtrain.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/advtrain.py

− removed
    as the second ("q") -- the opposite argument order from TRADES."""
    raise NotImplementedError("implement kl_at_loss")
+ added
    as the second ("q") -- the opposite argument order from TRADES."""
    cl = model(Tensor(np.asarray(x_clean, dtype=np.float64)))
    ad = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    ce = ag.cross_entropy(ad, y)
    tgt = _detach(cl)
    kl = ag.kl_div(ad, tgt)
    loss = ag.add(ce, ag.mul(kl, float(beta)))
    return loss, {"ce": float(ce.data), "kl": float(kl.data), "loss": float(loss.data)}

contents
The file /app/submission/advtrain.py has been updated successfully. (file state is current in your context , no need to Read it back)

/app/submission/advtrain.py

− removed
    """AT with logit squeezing: L = CE(adv,y) + lam*mean(z_adv**2) (penalize large logits)."""
    raise NotImplementedError("implement logit_squeeze_at_loss")


def ls_at_loss(model, x_adv: np.ndarray, y: np.ndarray,
               eps_ls: float = 0.1) -> Tuple[Tensor, Dict[str, float]]:
    """Label-smoothed AT: L = label_smoothed_ce(model(adv), y, eps_ls)."""
    raise NotImplementedError("implement ls_at_loss")
+ added
    """AT with logit squeezing: L = CE(adv,y) + lam*mean(z_adv**2) (penalize large logits)."""
    za = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    ce = ag.cross_entropy(za, y)
    sq = ag.mean(ag.mul(za, za))
    loss = ag.add(ce, ag.mul(sq, float(lam)))
    return loss, {"ce": float(ce.data), "sq": float(sq.data), "loss": float(loss.data)}


def ls_at_loss(model, x_adv: np.ndarray, y: np.ndarray,
               eps_ls: float = 0.1) -> Tuple[Tensor, Dict[str, float]]:
    """Label-smoothed AT: L = label_smoothed_ce(model(adv), y, eps_ls)."""
    za = model(Tensor(np.asarray(x_adv, dtype=np.float64)))
    loss = label_smoothed_ce(za, y, eps_ls)
    return loss, {"loss": float(loss.data)}

contents
The file /app/submission/advtrain.py has been updated successfully. (file state is current in your context , no need to Read it back)
shell
python3 run_checks.py --only advtrain 2>&1 | tail -25 && echo "===INTEGRATION===" && python3 run_checks.py --only integration 2>&1 | tail -8
output
[advtrain]  14/14
  advtrain/at_param_grad                   OK    (max_abs=2.56e-11)
  advtrain/trades_param_grad               OK    (max_abs=5.66e-04)
  advtrain/mart_param_grad                 OK    (max_abs=1.14e-04)
  advtrain/alp_param_grad                  OK    (max_abs=2.60e-11)
  advtrain/robust_ce_param_grad            OK    (max_abs=4.29e-11)
  advtrain/clp_param_grad                  OK    (max_abs=2.84e-05)
  advtrain/kl_at_param_grad                OK    (max_abs=1.62e-03)
  advtrain/logit_squeeze_param_grad        OK    (max_abs=4.80e-11)
  advtrain/ls_at_param_grad                OK    (max_abs=2.76e-11)
  advtrain/label_smoothed_ce_grad          OK  
  advtrain/trades_stopgrad                 OK    (max_abs=0.00e+00)
  advtrain/alp_pairing                     OK    (max_abs=0.00e+00)
  advtrain/clp_stopgrad                    OK    (max_abs=0.00e+00)
  advtrain/kl_at_stopgrad                  OK    (max_abs=0.00e+00)

------------------------------------------------------------------------
advtrain 14/14
TOTAL  14/14 public checks passing
All public checks pass. Now make sure model.npz clears the held-out ROBUST-accuracy threshold; the grader re-checks with DIFFERENT seeds/shapes + its OWN strong PGD.
===INTEGRATION===
  integration/pgd_at_decreases             OK    (1.4247->1.3885)
  integration/trades_finite                OK    (1.393->1.337)
  integration/trades_decreases             OK    (1.3933->1.3367)

---------------------------------------------
…[truncated 242 chars]
All public checks pass. Let me run the full suite to confirm:
shell
python3 run_checks.py 2>&1 | tail -5
output
------------------------------------------------------------------------
autograd_grads 82/82 | nn_forward 22/22 | optim 20/20 | attack 18/18 | advtrain 14/14 | integration 4/4 | data 3/3
TOTAL  163/163 public checks passing
All public checks pass. Now make sure model.npz clears the held-out ROBUST-accuracy threshold; the grader re-checks with DIFFERENT seeds/shapes + its OWN strong PGD.
All 163 public checks pass. Now let me write the training loop. First let me check the data and forbidden imports, plus timing.
shell
cat test.sh && echo "---" && grep -rEl "torch|jax|tensorflow|tinygrad|micrograd|autograd_lib|^import autograd$" submission/*.py 2>/dev/null; echo "checking imports done"
output
#!/usr/bin/env bash
# Smoke test (NOT the grader): confirms the environment is wired -- numpy imports, the training
# split loads, and the submission stubs are present. It does NOT check correctness (the stubs raise
# NotImplementedError until you implement them).
set -uo pipefail

python3 - <<'PY'
import numpy as np, os
p = "/app/data/train.npz"
assert os.path.exists(p), "missing train.npz"
d = np.load(p)
print(f"train.npz: X{d['X'].shape} {d['X'].dtype}  y{d['y'].shape}  classes={len(set(d['y'].tolist()))}")
for f in ("autograd.py", "nn.py", "optim.py", "data.py", "attack.py", "advtrain.py", "train.py"):
    assert os.path.exists(f"/app/submission/{f}"), f"missing /app/submission/{f}"
assert os.path.exists("/app/run_checks.py"), "missing /app/run_checks.py (public component runner)"
print("submission stubs present:", sorted(os.listdir("/app/submission")))
print("numpy", np.__version__)
PY
echo "app_test smoke OK (run 'python3 /app/run_checks.py' for the per-check progress report)"
---
submission/nn.py
checking imports done
All 163 public checks pass. Note `import autograd` in nn.py is the local module (required by design). Now the training loop:

/app/submission/train.py

− removed
def train(train_path, out_path, epochs=12, batch_size=128, lr=1.2e-3, eps=0.12,
          at_steps=7, alpha=0.03, grad_clip=1.0, weight_decay=5e-4, val_frac=0.15,
          sel_steps=7, seed=0, log_every=1):
    """Run multi-step PGD adversarial training and save the best-by-robust-val checkpoint to
    ``out_path``. See the module docstring for the recipe."""
    raise NotImplementedError("implement the adversarial-training loop")
+ added
def _robust_acc(model, X, y, eps, steps, alpha, restarts, rng, batch=256):
    """Worst-case robust accuracy under multi-restart PGD on (X, y)."""
    n = X.shape[0]
    correct = np.zeros(n, dtype=bool)
    # clean correctness first
    for s in range(0, n, batch):
        xb = X[s:s + batch]
        logits = model(A.Tensor(xb)).data
        correct[s:s + batch] = (logits.argmax(1) == y[s:s + batch])
    robust = correct.copy()
    for s in range(0, n, batch):
        xb = X[s:s + batch]; yb = y[s:s + batch]
        sl = slice(s, s + batch)
        if not robust[sl].any():
            continue
        xadv = A.pgd_restarts(model, xb, yb, eps, steps, alpha, restarts=restarts, rng=rng)
        pred = model(A.Tensor(xadv)).data.argmax(1)
        robust[sl] = robust[sl] & (pred == yb)
    return float(robust.mean())


def train(train_path, out_path, epochs=30, batch_size=128, lr=1e-3, eps=0.12,
          at_steps=10, alpha=0.03, grad_clip=1.0, weight_decay=5e-4, val_frac=0.12,
          sel_steps=10, seed=0, log_every=1):
    """Run multi-step PGD adversarial training and save the best-by-robust-val checkpoint to
    ``out_path``. See the module docstring for the recipe."""
    rng = np.random.default_rng(seed)
    X, y = D.load_npz(train_path)
    n_classes = int(y.max()) + 1
    c_in, img = X.shape[1], X.shape[2]
    (Xtr, ytr), (Xval, yval) = D.train_val_split(X, y, val_frac, rng)
    print(f"data: train={Xtr.shape} val={Xval.shape} classes={n_classes} img={img} c_in={c_in}")
…[truncated 1889 chars]

contents
The file /app/submission/train.py has been updated successfully. (file state is current in your context , no need to Read it back)
Let me first time a single epoch to gauge the budget:
shell
cd /app/submission && time python3 -c "
import train as Tr
import numpy as np
sd, br = Tr.train('/app/data/train.npz', '/tmp/test_model.npz', epochs=1, seed=0)
" 2>&1 | tail -15
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
=== SyncVals verifier (local re-grade of the agent's own checkpoint) ===

COMPONENT CONFORMANCE SUITE: 201/201 cases passed  (all milestones pass: True)
FINAL METRIC: PGD robust accuracy = 0.5675  < threshold 0.6

REWARD = 0   (1 iff every component milestone passes AND the sealed held-out metric clears its threshold)

NOTE: the in-sandbox training in the 481MB e2b box was OOM-killed (0-byte checkpoint), so the raw
in-sandbox reward was an infrastructure artifact. This reward is from a faithful LOCAL re-train of the
agent's OWN train.py (24GB, no OOM) with its own default hyperparameters, then re-graded by the real verifier.

Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_17b58591aaf6490f. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.

Trial trial_17b58591aaf6490f · verifier authoritative; classifier explanatory.