Session Lifecycle

Ask Caddie calls /api/lectures/{id}/copilot/start, which provisions a private Daily WebRTC room and mints separate user and bot owner tokens. The Pipecat bot joins via the VM sidecar (/start/lecture) with lecture_data carrying the full sections[] manifest and concept_graph. Gemini Live 2.5 handles bidirectional audio natively — no intermediate transcription step.

Grounding & Memory

At startup, each section[] title is embedded and vector-searched against articles_scored in a background precompute task — top 3 feed articles per section are cached in memory, injected deterministically when the user pauses on that section. YouTube currentTime anchors every response to the active temporal section. Sessions persist via Redis: on disconnect, Gemini Flash summarizes the conversation into a structured continuity packet {learned, struggling, open_threads} scoped to (article_id, client_id) with a 24h TTL — loaded as model context on the next session.