Singligent: curated human single-cell RNA-seq metadata catalog

Harmonized, ontology-aligned, deduplicated METADATA for 943,732 human scRNA-seq samples aggregated from 8 archives (GEO, EGA, NCBI, EBI BioStudies, CellxGene, PsychAD, HTAN, HCA), exposed at four record levels (samples, projects, series, cell types). Produced by Singligent (Nanjing University; portal https://biobigdata.nju.edu.cn/singligent/ , lab https://compbio.nju.edu.cn/ ). This is the metadata compilation only — raw sequencing data remain at the source archives (EGA: metadata-only; data access requires DAC approval). Tables are provided as Parquet + gzipped CSV, plus the full SQLite snapshot, a data dictionary and SHA-256 checksums. See README.md.