Pipe hn into scripts

Every command emits structured records, and in a pipe the default format is JSONL: one JSON object per line. That makes hn a clean source for jq and ordinary shell tools.

One object per line

hn top -n10 | jq -r '.title'
hn top -n50 | jq -r 'select(.score > 300) | .url'

Because the default adapts to the destination, you do not pass -o for this. At a terminal the same command prints a table; in a pipe it prints JSONL.

A whole result as one array

When a tool wants a single JSON document rather than a stream, use -o json:

hn search "rust" -n100 -o json | jq 'length'

Templates for custom lines

For full control over each line without jq, apply a Go text/template. The fields are the lowercase JSON keys:

hn top -n10 --template '{{.score}}  {{.title}}'
hn top -n10 --template '{{.by}} -> {{.hn_url}}'

CSV for spreadsheets

hn ask -n100 --fields score,comments,title -o csv > ask.csv
hn ask -n100 --fields score,comments,title -o csv --no-header >> running.csv

Exit codes in scripts

hn distinguishes "found nothing" from "broke":

if hn search "a-term-with-no-hits" -q >/dev/null; then
  echo "had results"
else
  case $? in
    3) echo "no results" ;;
    *) echo "request failed" ;;
  esac
fi

See troubleshooting for the full exit-code table.