mod-008a-model-missing-constructor-attributes-tests

A testing rule for machine-learning models in PhysicsNeMo, a Python library for physics-based machine learning. It requires tests for creating each model and checking its public settings.

In plain words
What is it for?
Use it when adding or updating models in PhysicsNeMo. It guides pytest tests for default and custom arguments and checks each public attribute.
Why use it?
It catches broken constructors and incorrectly initialized settings across different model configurations before they cause problems.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/nvidia/physicsnemo/mod-008a-model-missing-constructor-attributes-tests
Clone the repo
git clone --depth 1 https://github.com/NVIDIA/physicsnemo

Made for: Cursor.

Per session 25 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 474 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00025 $0.00474
Opus 5 $0.00013 $0.00237
Sonnet 5 $0.00005 $0.00095
Haiku 4.5 $0.00003 $0.00047

Measured 2d ago against content hash c94297c54758, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mod-008a-model-missing-constructor-attributes-tests scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/mod-008a-model-missing-constructor-attributes-tests.mdc · 70 lines

What it actually says

When creating tests for models, rule MOD-008a must be followed. Explicitly reference "Following rule MOD-008a, which requires constructor and attribute tests..." when implementing test cases.

MOD-008a: Model missing constructor/attributes tests

Description:

Every model in physicsnemo/nn or physicsnemo/models must have tests that verify model instantiation and all public attributes (excluding buffers and parameters).

These tests should:

  • Use pytest parameterization to test at least 2 configurations
  • Test one configuration with all default arguments
  • Test another configuration with non-default arguments
  • Verify all public attributes have expected values

Rationale:

Constructor tests ensure the model can be instantiated correctly with various configurations and that all attributes are properly initialized. This catches issues early in the development cycle.

Example:

@pytest.mark.parametrize(
    "config",
    ["default", "custom"],
    ids=["with_defaults", "with_custom_args"]
)
def test_my_model_constructor(config):
    """Test model constructor and attributes."""
    if config == "default":
        model = MyModel(input_dim=64, output_dim=32)
        assert model.hidden_dim == 128  # Default value
        assert model.dropout == 0.0  # Default value
    else:
        model = MyModel(
            input_dim=64,
            output_dim=32,
            hidden_dim=256,
            dropout=0.1
        )
        assert model.hidden_dim == 256
        assert model.dropout == 0.1

    # Test common attributes
    assert model.input_dim == 64
    assert model.output_dim == 32

Anti-pattern:

# WRONG: Only testing default configuration
def test_my_model_bad():
    model = MyModel(input_dim=64, output_dim=32)
    # Only tests defaults, not custom configurations

# WRONG: Not verifying attributes
def test_my_model_bad():
    model = MyModel(input_dim=64, output_dim=32)
    # Model created but attributes not tested
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 70 lines · 25 tokens per session scan A c94297c54758

Subscribe to this mod's changes

mod-008a-model-missing-constructor-attributes-tests is a cursor rule published in the GitHub repository NVIDIA/physicsnemo (3,211 stars, last pushed today), licensed Apache-2.0. It adds 25 tokens to every session and 474 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.