Quick trivia

Every other demo pushes UI one direction: the agent draws, the screen shows. This one lets the caller edit what is on screen and sends the change back to the agent. It is a three-question trivia game whose quiz you can retype in the panel or change by voice, then play.

The voice path is the repo default: Deepgram Nova-3 for STT, gpt-4o-mini for grading and flow, Cartesia Sonic-2 for the host. The model, not code, decides whether an answer is right and accepts paraphrases.

The new piece is the reverse channel. The agent publishes the quiz as an EditableTable, and edits come back on a ui_action topic, the mirror of the forward ui channel the agent publishes on:

@ctx.room.on("data_received")
def on_ui_action(packet: rtc.DataPacket) -> None:
    if packet.topic != UI_ACTION_TOPIC or userdata["started"]:
        return
    envelope = json.loads(packet.data.decode("utf-8"))
    if envelope.get("id") != "quiz" or envelope.get("action") != "submit":
        return
    rows = (envelope.get("payload") or {}).get("rows")
    if _apply_quiz_edit(userdata, rows):
        _publish_quiz_editor(ctx.room, userdata)

A set_question tool mutates the same userdata from voice, so typing and telling the host hit one source of truth and can never disagree.

The edit application is defensive: a half-finished grid must never wipe a question, so a blanked cell falls back to the current value and the row count stays fixed:

q = str(row[0]).strip() if len(row) > 0 else ""
a = str(row[1]).strip() if len(row) > 1 else ""
updated.append({"q": q or item["q"], "a": a or item["a"]})

Play runs on two tools: ask_question shows a Card and hands the model the answer to judge, and score_answer records the result. score_answer keeps a set of already-scored questions, so the total can never run past three.

The reverse channel is just another data topic. Publish interactive UI on ui, subscribe to ui_action for what comes back, and match on the component's id and action so you only react to the control you meant to.

Build it from an empty folder in the full walkthrough, or talk to the finished agent at https://playground.mahimai.ca/demos/quick-trivia.