Started fix/fk/artefact-download-fallback from virdx/mono main, then corrected the behavior after clarifying the function contract.
Reduced ArtefactsNamespace.download to a two-line guard that raises ValueError when any attachment URL is not Parquet; normal Parquet behavior is unchanged.
Ran the vxData SDK formatter, linter, type checker, all 38 tests, and pre-commit checks.
Amended and force-pushed commit b6a453ba; updated virdx/mono#351 to a one-line description.
Lessons Learned: Pitfalls
The initial fallback misunderstood the method contract by introducing a mixed DataFrame/path return type. Clarifying whether a helper is a generic materializer or a format-specific reader before implementation would have avoided that expansion.
Lessons Learned: Improvements
Document ArtefactsNamespace.download as Parquet-only and direct callers with arbitrary attachments to client.storage.download.
