NCBIDatasets List Genomes By Taxon

List genome assemblies available for a taxon (NCBI tax id or scientific name) via the NCBI Datasets v2 API. Returns a summary list of assemblies (accession, assembly name/level, RefSeq category, release date, total length, N50, GC%) plus the total count available. Use to discover what genomes exist for an organism or clade, e.g. all Escherichia coli or Mycobacterium tuberculosis assemblies. Set reference_only to restrict to reference/representative genomes. No API key required.