docs: add AGENTS.md

Author: hakandilek

AGENTS.md

@@ -0,0 +1,53 @@
+# AGENTS.md
+
+Library wrapping [`cyclonedx-python-lib`](https://github.com/CycloneDX/cyclonedx-python-lib) to 
+read/write Siemens [Standard BOM](https://sbom.siemens.io/latest/format.html) 
+(a CycloneDX-compatible SBOM format). Source in [`siemens_standard_bom/`](siemens_standard_bom/).
+
+## Commands (run from repo root)
+
+- Full check (lint + type + tests, Python 3.10-3.14): `poetry run tox run`
+- Lint + types only: `poetry run tox run -e lint,type`
+- Tests on one interpreter: `poetry run tox run -e 3.12`
+- Single test: `poetry run python -m unittest tests.test_v3_parser.SbomV3ParserTestCase.test_read_sunny_day`
+
+Config: 
+- [`tox.toml`](tox.toml), 
+- [`pyproject.toml`](pyproject.toml), 
+- [`.flake8`](.flake8), 
+- [`.mypy.ini`](.mypy.ini).
+
+## Testing
+
+- Uses stdlib [`unittest`](https://docs.python.org/3/library/unittest.html) (via `unittest discover`), 
+    NOT [pytest](https://docs.pytest.org/).
+- Run from repo root only: tests read fixtures by relative path ([`tests/v2/`](tests/v2/), 
+    [`tests/v3/`](tests/v3/)) and write to `output/` at repo root (gitignored, auto-created).
+- Comparison tests use [`deepdiff`](https://github.com/seperman/deepdiff) and intentionally exclude 
+    `bom_ref` values from diffs ([`tests/abstract_sbom_compare.py`](tests/abstract_sbom_compare.py)).
+
+## Architecture
+
+- Thin wrapper: `StandardBom` wraps `cyclonedx.model.bom.Bom`; `SbomComponent`/`SourceArtifact`
+    /`ExternalComponent` wrap CycloneDX models. Reach the underlying object via `.bom` / `.component`. 
+    See [`model.py`](siemens_standard_bom/model.py).
+- Siemens-specific fields are NOT native CycloneDX: they're stored as `Property` entries keyed 
+    `siemens:*` (constants at top of [`model.py`](siemens_standard_bom/model.py)) or as typed 
+    `ExternalReference`s. Add a field by adding a constant + property getter/setter following existing 
+    patterns.
+- Reader supports BOTH v2 and v3 Standard BOM (see backward-compat branches in the `tools`/`authors` 
+    getters); keep both working.
+- Output is always CycloneDX JSON v1.6 (`JsonV1Dot6`). 
+    [`StandardBomParser.save(..., with_dependencies=False)`](siemens_standard_bom/parser.py) re-reads 
+    and strips `dependencies` from the file (prohibited in the 
+    [`external` profile](https://sbom.siemens.io/v3/profiles.html)).
+
+## Conventions
+
+- [mypy](https://mypy.readthedocs.io/en/stable/) `strict = True`, `implicit_reexport = False`; 
+- [flake8](https://flake8.pycqa.org/) max line length 140, max complexity 8, doctests checked.
+- Requires Python >=3.10,<4.0 and [Poetry](https://python-poetry.org/) >= 2.0.
+- Release: bump `version` in [`pyproject.toml`](pyproject.toml); pushing a `vX.Y.Z` tag publishes 
+    to [PyPI](https://pypi.org/p/siemens-standard-bom) (see [`release.yml`](.github/workflows/release.yml)). 
+- The self tool-entry version reads from installed package metadata, so `poetry install` 
+    the package for it to report correctly.