Common patterns

Fallback for a value that might be absent

The summary is null unless the contextual metadata output has summary generation enabled, so don't build a prompt that assumes it. Test for null with != null: $exists() returns true for a field whose value is null.

media.contextual.summary != null
  ? media.contextual.summary
  : $join(media.contextual.objects, ", ")

Skipping an empty window

A window with no speech produces an empty transcript. Send the model something meaningful instead of an empty prompt.

$exists(media.transcript) and $length($trim(media.transcript)) > 0
  ? "Summarize: " & media.transcript
  : "No speech in this window."

Flattening clips into one line of prompt

$join(media.clip.events.(keyword & ": " & description), "\n")

Extracting a structured answer

Ask the model for JSON in the request expression, then parse it in the response expression so that the stored value is data.

/* in the request expression */
{ "text": "Answer as JSON with keys sentiment and reason. Transcript: " & media.transcript }

/* in the response expression */
$parse(content[type = "text"][0].text)

Guarding a response expression

A model can return a truncated or unexpected response. A response expression that finds nothing stores nothing useful, so provide a fallback.

(
  $text := content[type = "text"][0].text;
  $exists($text) ? { "result": $text } : { "note": "empty model response" }
)