radianceded
### Issue Origin Found while running the unit suite locally on Windows (OpenViking `main` @ `1394d4769`, 2026-10-01). ### Bug Description `tests/unit/test_skill_processor_windows_paths.py::test_write_auxiliary_files_normalizes_windows_separators` (introduced with #5018, 2026-09-17) cannot pass on **any** platform: **Windows** — the fixture writes `base_path / "scripts\check_bounding_boxes.py"` without creating the `scripts` directory first, so it fails with `FileNotFoundError` before reaching any assertion: ``` FileNotFoundError: [Errno 2] No such file or directory: '...\pdf\scripts\check_bounding_boxes.py' ``` **POSIX** — the backslash is a legal filename character there, so the fixture creates ONE file whose name contains a literal backslash. `rel_path.as_posix()` never converts it, and the assertion expecting `.../scripts/check_bounding_boxes.py` fails because the stored URI keeps the raw backslash. So the normalization the test name promises is only accidentally correct on Windows (via `Path` construction), and the POSIX literal-backslash case is entirely unguarded. ### Why it went unnoticed The unit suite (`tests/unit`) is not part of the pull-request checks (`pr.yml` runs SDK / langchain / cuVS / plugin tests only), and `_test_full.yml` — the only workflow that exercises it across OSes — was last dispatched manually in March 2026. ### Suggested fix 1. Fixture: create `scripts/` and model the extracted artifact with real path segments; move the literal-backslash name into a POSIX-only case (`@pytest.mark.skipif(os.name == "nt", ...)`), since Windows cannot create such a file name. 2. Implementation: `_write_auxiliary_files` should normalize explicitly (`rel_uri_path.replace("\\", "/")`) instead of relying on `as_posix()` platform behavior, so a literal-backslash name extracted on Linux is still stored as a forward-slash URI. I have a fix ready and will open a PR referencing this issue.