UI event types in the stream (Card, Row, Pressable …) stream/card

What it is

The answer stream (POST /f/conversation, server-sent events) carried about 16 event types until 21 Aug 2026: deltas, search_model_queries, search_result_group, sources_footnote, title_generation, message_stream_complete. On 22 Aug, types named after UI elements were added. They do not appear everywhere but only on questions with a widget: Card, Col, Each, Icon, Pressable, Row, Show, Spacer, Svg, Text on the two local questions K1-01 and K1-02 (location map, ask_user_location_v2), the smaller set Basic, Box, Button additionally on K3-02 and K5-01. They travel with the widget, not with the answer in general. What they carry has not been analysed yet; har-analyzer.js records type names only, not content.

External evidence

None. The tracker saw this first; status observed since 22 Aug 2026.

For visibility

No proven effect. The open question is whether this is the beginning of an answer form where links sit in components rather than in text.

Change history

Open

• A layout vocabulary (Row, Col, Card, Pressable) in the answer stream — a precursor of a generated interface (genui) instead of Markdown? Together with the new endpoint widget_server_action on the same day and widget questions as the only place they occur.
• The types appear only on widget questions (2–4 of 33). Are they the building blocks a widget is assembled from in the stream? The new endpoint widget_server_action on the same day fits that.

Related

Widgets (genui, dil, map, nav_list) entity (entity markup)