# Reference Model 문서 작성 가이드

이 디렉터리는 Reference Model Agent가 작성하거나 제안한 기능별 reference model 설계 문서를 보관하는 위치다.

Reference Model Agent는 FESA 기능 검증에 필요한 Abaqus `.inp` 기반 테스트 모델 포트폴리오와 `references/<feature-id>/<model-id>/` artifact bundle 계약을 정의한다. Agent는 Abaqus, Nastran 또는 레퍼런스 솔버를 직접 실행하지 않고, reference CSV 값을 생성하지 않으며, solver 결과 비교나 release readiness 승인도 하지 않는다.

기본 파일명은 `docs/reference-models/<feature-id>-reference-models.md` 형식을 사용한다. 각 문서는 요구조건, 연구 브리프, 정식화, 수치 리뷰, I/O 정의를 입력으로 받아 구현 전에 준비해야 할 테스트 모델과 reference artifact 요구사항을 정의해야 한다.

## Reference Model Agent 역할

수행한다:
- 기능별 reference model portfolio를 smoke, analytical, patch test, benchmark, regression, negative/invalid-input model로 구분한다.
- `model.inp`가 I/O Definition Agent의 supported Abaqus keyword subset 안에 있는지 확인한다.
- `references/<feature-id>/<model-id>/` artifact bundle 구조와 필수 파일을 정의한다.
- `metadata.json` provenance, 단위, 좌표계, Abaqus version/source, output request, tolerance 정책을 정의한다.
- `displacements.csv`, `reactions.csv`, `element_forces.csv`, `stresses.csv` 요구사항을 정의한다.
- requirement와 model, compared quantity, tolerance, artifact status를 연결하는 Coverage Matrix를 작성한다.

수행하지 않는다:
- C++ 코드를 구현하지 않는다.
- parser를 구현하지 않는다.
- C++ API나 파일 구조를 설계하지 않는다.
- Abaqus, Nastran 또는 레퍼런스 솔버를 직접 실행하지 않는다.
- reference CSV를 생성하지 않는다.
- solver 결과를 비교하지 않는다.
- release readiness를 승인하지 않는다.
- reference 값, tolerance, Abaqus compatibility를 임의로 만들지 않는다.

## 문서 템플릿

```markdown
# <feature title> Reference Models

## Metadata
- feature_id: <feature-id>
- source_requirement: docs/requirements/<feature-id>.md
- source_research: docs/research/<feature-id>-research.md
- source_formulation: docs/formulations/<feature-id>-formulation.md
- source_numerical_review: docs/numerical-reviews/<feature-id>-review.md
- source_io_definition: docs/io-definitions/<feature-id>-io.md
- status: draft | needs-user-decision | needs-reference-artifacts | ready-for-implementation-planning | blocked
- owner_agent: reference-model-agent
- date: <YYYY-MM-DD>

## Reference Strategy
- verification_scope: <feature verification purpose>
- code_verification: <unit/math-level checks supported by this portfolio>
- solution_verification: <mesh, convergence, patch, or analytical checks>
- benchmark_reference_comparison: <Abaqus/NAFEMS/NASA/paper-derived comparison plan>
- excluded_validation_scope: <physical experiment validation excluded unless explicitly available>

## Model Inventory

| model_id | category | purpose | status | required_artifacts |
| --- | --- | --- | --- | --- |
| <model-id> | smoke | <basic parser/solve path> | draft | model.inp, metadata.json, required CSVs |
| <model-id> | analytical | <closed-form comparison> | draft | model.inp, metadata.json, required CSVs |
| <model-id> | patch test | <element consistency check> | draft | model.inp, metadata.json, required CSVs |
| <model-id> | benchmark | <trusted benchmark comparison> | draft | model.inp, metadata.json, required CSVs |
| <model-id> | regression | <known defect guard> | draft | model.inp, metadata.json, required CSVs |
| <model-id> | negative/invalid-input | <unsupported keyword or invalid model diagnostic> | draft | model.inp, metadata.json |

## Model Record

### <model-id>
- category: smoke | analytical | patch test | benchmark | regression | negative/invalid-input
- purpose: <what this model proves>
- verified_requirements: [<requirement-id>]
- analysis_type: <linear static | nonlinear static | modal | other>
- element_type: <Abaqus element type and FESA feature element>
- material: <material model and values>
- boundary_conditions: <BC summary>
- loads: <load summary>
- expected_physical_quantities: displacement | reaction | element force | stress | strain | energy | residual
- tolerance: <absolute/relative/norm policy or needs-user-decision>
- source: <user | analytical | Abaqus Verification Guide | Abaqus Benchmarks Guide | NAFEMS | NASA/FEMCI | paper>
- artifact_status: draft | needs-reference-artifacts | ready-for-implementation-planning | blocked

## Abaqus Input Requirements
- input_file: references/<feature-id>/<model-id>/model.inp
- supported_keyword_subset: <keywords from docs/io-definitions/<feature-id>-io.md>
- model_data: <nodes, elements, sets, material, section, coordinates, units>
- history_data: <step, procedure, boundary conditions, loads, output requests>
- output_requests: <requests needed to populate reference CSV files>
- unsupported_keyword_policy: unsupported | ignored-with-warning | requires-user-decision

## Artifact Bundle Contract

```text
references/
  <feature-id>/
    <model-id>/
      model.inp
      metadata.json
      displacements.csv
      reactions.csv
      element_forces.csv
      stresses.csv
      README.md
```

Required files:
- `model.inp`: Abaqus input file for the reference model.
- `metadata.json`: provenance and model contract metadata.
- `displacements.csv`: nodal displacement reference results.
- `reactions.csv`: nodal reaction force reference results.
- `element_forces.csv`: element internal force reference results.
- `stresses.csv`: stress reference results.
- `README.md`: short description, generation notes, and limitations.

Optional files:
- `strains.csv`: strain reference results when required.
- `energy_or_residual.csv`: energy, residual, or convergence reference results when required.
- `notes.md`: manual review notes.

## Metadata JSON Contract

```json
{
  "feature_id": "<feature-id>",
  "model_id": "<model-id>",
  "artifact_status": "draft | needs-reference-artifacts | ready-for-implementation-planning | blocked",
  "abaqus_version": "<version or needs-user-decision>",
  "generation_owner": "<person/procedure>",
  "generation_date": "<YYYY-MM-DD>",
  "source_documents": ["docs/requirements/<feature-id>.md"],
  "units": "<unit system>",
  "coordinate_system": "global Cartesian unless otherwise documented",
  "analysis_type": "<analysis type>",
  "element_types": ["<Abaqus element type>"],
  "material_values": {},
  "boundary_condition_summary": "<summary>",
  "load_summary": "<summary>",
  "output_requests": ["U", "RF", "S", "<feature-specific quantities>"],
  "csv_schema_version": "<version>",
  "tolerance_policy": "<absolute/relative/norm policy>",
  "limitations": ["<known limitation>"]
}
```

## Reference CSV Requirements

### displacements.csv
- Required when nodal displacement is a verification quantity.
- Must include step/frame identity, node id, displacement components, coordinate system, and units.

### reactions.csv
- Required when constrained DOF reactions or global equilibrium are verification quantities.
- Must include step/frame identity, node id, reaction components, coordinate system, and units.

### element_forces.csv
- Required when element internal force is a verification quantity.
- Must include step/frame identity, element id, output location, component, value, and units.

### stresses.csv
- Required when stress is a verification quantity.
- Must include step/frame identity, element id, integration point or recovery location, component, value, coordinate system, and units.

### Optional CSVs
- `strains.csv`: required when strain is part of the acceptance criteria.
- `energy_or_residual.csv`: required when energy balance, residual, or convergence data is part of the acceptance criteria.

## Coverage Matrix

| requirement_id | model_id | compared_quantity | artifact_file | tolerance | verification_method | status |
| --- | --- | --- | --- | --- | --- | --- |
| <req-id> | <model-id> | displacement | displacements.csv | <policy> | reference-comparison | draft |
| <req-id> | <model-id> | reaction | reactions.csv | <policy> | reference-comparison | draft |
| <req-id> | <model-id> | element force | element_forces.csv | <policy> | reference-comparison | draft |
| <req-id> | <model-id> | stress | stresses.csv | <policy> | reference-comparison | draft |

## Artifact Acceptance Checklist
- 모든 `must` requirement가 최소 하나의 `model_id`와 `compared_quantity`에 연결되어 있다.
- `model.inp`가 기능별 supported Abaqus keyword subset을 벗어나지 않는다.
- `metadata.json`에 provenance, Abaqus version/source, units, coordinate system, tolerance, CSV schema version이 기록되어 있다.
- 필수 CSV 파일이 존재하거나, 기능상 불필요한 파일은 명확한 reason과 함께 제외되어 있다.
- output request가 필요한 CSV 물리량을 생성할 수 있도록 정의되어 있다.
- reference CSV가 없으면 status는 `needs-reference-artifacts`다.
- tolerance, source, units, coordinate system이 불명확하면 status는 `needs-user-decision`이다.

## Open Issues and Downstream Handoff

### I/O Definition Agent
- <supported keyword, output request, CSV schema clarification>

### Implementation Planning Agent
- <tests that should fail before implementation, model order, acceptance criteria>

### Reference Verification Agent
- <CSV schema, ID matching, units, coordinate conventions, output locations, tolerance mapping>

### Physics Evaluation Agent
- <equilibrium, symmetry, displacement direction, stress location, rigid body mode, load path sanity checks>
```

## 품질 기준

- Reference model의 목적과 검증 대상 requirement가 명확해야 한다.
- `model.inp`는 Abaqus input file이며, 기능별 supported keyword subset을 따라야 한다.
- model data와 history data를 구분해야 한다.
- output request와 required CSV 사이의 연결이 명확해야 한다.
- `references/<feature-id>/<model-id>/` 구조와 필수 artifact가 명시되어야 한다.
- `metadata.json`에는 provenance, Abaqus version/source, units, coordinate system, tolerance, CSV schema version이 포함되어야 한다.
- reference CSV가 없으면 완료 상태가 아니라 `needs-reference-artifacts` 상태로 둔다.
- 모든 `must` requirement는 Coverage Matrix에서 model, compared quantity, tolerance, verification method로 추적되어야 한다.

## Abaqus UserSubroutine artifact metadata v1

For Fortran Abaqus UserSubroutine work, each stored artifact bundle may include `metadata.json` with:

```json
{
  "schema_version": "abaqus-user-subroutine-artifact-v1",
  "feature_id": "<feature-id>",
  "model_id": "<model-id>",
  "artifact_status": "draft | needs-reference-artifacts | ready-for-comparison | blocked",
  "abaqus": {
    "version": "<Abaqus version>",
    "precision": "single | double",
    "command": "abaqus job=<job> user=<subroutine>"
  },
  "compiler": {
    "vendor": "Intel oneAPI",
    "name": "ifx | ifort",
    "version": "<compiler version>"
  },
  "subroutine": {
    "entry_points": ["UMAT"],
    "source_files": [
      {
        "path": "src/fortran/abaqus/UMAT.for",
        "language": "Fortran",
        "sha256": "<source sha256>"
      }
    ]
  },
  "input_file": "model.inp",
  "outputs": {
    "tails": {
      "msg": "job.msg.tail.txt",
      "dat": "job.dat.tail.txt",
      "log": "job.log.tail.txt"
    },
    "csv": {
      "stresses": "stresses.csv"
    }
  }
}
```

`artifact_status=ready-for-comparison` means `scripts/validate_reference_artifacts.py` must find all declared files and confirm source SHA-256 values. Agents must not generate or edit the declared reference CSVs unless an explicit reference-artifact phase authorizes that work.