on_files() (and therefore on_download(), which lists files before
fetching) no longer fails with HTTP 400 GRAPHQL_VALIDATION_FAILED. The
getFiles query requested a key field that the current OpenNeuro schema
no longer exposes on DatasetFile; the query now requests id (the
directory tree token) and urls (direct HTTPS download links) instead
(#1).on_files() now returns an id column (the token to pass back as tree
when recursing into a directory) and a urls list column. The key
column is retained as a backward-compatible alias of id.GRAPHQL_VALIDATION_FAILED reason) is now surfaced, and genuine
connectivity failures remain distinct (#1).on_doctor() and backend auto-selection no longer treat a broken AWS CLI
as available. The S3 backend check now runs aws --version and requires a
clean exit, instead of only looking for the aws binary on PATH (#1).Search and explore OpenNeuro datasets via GraphQL API
on_search() - Full-text and modality-based searchon_dataset() - Detailed metadata retrievalon_snapshots() - List version historyon_files() - Browse file treesDownload datasets with multi-backend support
on_download() - Download files with automatic backend selectionCRAN-compliant caching with manifest tracking
on_cache_list(), on_cache_info(), on_cache_clear()tools::R_user_dir()Lazy handle pattern for pipeline integration
on_handle() - Create lazy dataset referenceson_fetch() - Materialize data when neededon_path() - Get local paths for immediate useDeveloper utilities
on_client() - Create and configure API clientson_doctor() - Diagnose backend availability