Agent Answer Streaming (LISTEN/NOTIFY)

中文 · English

Status: implemented. The Runtime and open API stream model text through model.delta events using PostgreSQL LISTEN/NOTIFY.

Data	Delivery	Replay behavior
Run lifecycle and tool progress	Durable runtime_events rows	Replayable with Last-Event-ID or after
Final answer	Persisted run output and run.completed	Always available after completion
Model text deltas	Transient notifications, never inserted into the event log	Best effort; no event ID and no replay

The internal SSE stream may include text and reasoning deltas. The public API forwards visible answer text only; reasoning and tool-call fragments remain internal. A disconnect or lost notification can degrade the experience to receiving the complete answer at completion, but does not change the durable result.

The Chinese design document retains the original design background and describes per-round rendering, delivery guarantees, and public/internal presentation rules.