Output Formatting

Most data commands take three flags for shaping output, meant for scripts and coding agents:

$
--json [fields]
$
--jq <expression>
$
--template <template>

JSON

--json prints the raw response:

$
bctrl runtime list --json

Add a comma-separated field list to keep only those keys:

$
bctrl runtime list --json id,status

On a list response, the projection applies to each object inside data.

jq

--jq filters the JSON with a jq expression and requires --json:

$
bctrl runtime list --json --jq '.data[].id'

The CLI bundles jq, so this flag works without a system jq installed.

Templates

--template formats the JSON with a Handlebars template and also requires --json:

$
bctrl runtime list \
>
  --json \
>
  --template '{{#each data}}{{id}} {{status}}{{newline}}{{/each}}'

A few extra helpers cover common formatting needs:

Rules

Because --jq and --template operate on the JSON response, passing either without --json is an error:

$
bctrl runtime list --jq '.data'
$
# error: cannot use --jq without specifying --json

Build scripts on JSON output. The human-oriented terminal text can change between releases, so do not parse it.