Use when fetching document summaries from NCBI Entrez databases by database name and identifier or accession
esummary/home/vimalinx/miniforge3/envs/bio/bin/esummary-mode json when downstream parsing prefers JSON over XML.esummary over efetch when you only need metadata, not the full payload.# 1) Assembly summary
esummary -db assembly -id GCF_000001405.40
# 2) SRA summary in JSON
esummary -db sra -id SRR5437876 -mode json
# 3) Search then summarize
esearch -db biosample -query 'SAMN03737421' | esummary
esearch or known accessions to get the relevant record IDs.-mode json only if your downstream tooling benefits from it.xtract on XML summaries when you need a quick tabular extract.esummary returns summaries, not full records or raw sequence payloads.einfo or esearch if unsure.-raw only when you know the database-specific XML rewriting is getting in your way.