The session_level_signals body field the feed surfaces carry: a session
state snapshot (surface navigation trail, video counters, ranking-session
window). app_session_navigation is the current screen plus when it came to
front, read from the navigation state; the ranking-session window derives
from the request clock (local hour, day, weekend); the session counters are
zero for a just-started cold session. Key order mirrors the 448 capture.
The
session_level_signalsbody field the feed surfaces carry: a session state snapshot (surface navigation trail, video counters, ranking-session window).app_session_navigationis the current screen plus when it came to front, read from the navigation state; the ranking-session window derives from the request clock (local hour, day, weekend); the session counters are zero for a just-started cold session. Key order mirrors the 448 capture.