Extend the panel engine with a layer loop: Fusion is one proposer round,
MoA runs N rounds where each round after the first sees the previous
round's responses via <previous_layer_responses> and refines its answer.
Only the final round is persisted; intermediate rounds are live-only.
Rounds are clamped to 1-5.
- SessionRecord + migration: moa_layers column (default 2)
- RunPanel: layer loop with per-member cloned message injection
- CloneForMember / BuildPreviousLayerBlock helpers for member isolation
- SSE: panel_layer_start / panel_layer_done events
- Frontend: layer_index composite keying, round dividers, MoA option
- Docs: ARCHITECTURE + ARCHITECTURE_QUICK updated
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Panel members now stream token-by-token and show tool uses in real time
(like the session agent) instead of delivering text only at completion.
The key constraint is byte-level safety: N members flushing SSE frames
concurrently on the shared HttpResponse would interleave and corrupt the
stream, so a SemaphoreSlim gate serializes the writes (not the model work).
- SseHelper.TryWriteSse takes an optional write-lock (default null, backward
compatible)
- NonStreamingLoopCallbacks carries SseGate + MemberIndex; _text/_tool/_error
events are tagged with the member index (review/finalizer stay at -1, no gate)
- CLI members forward TextDelta/ToolStart/ToolResult live instead of
discarding everything but the final text
- Anthropic-API members stream per tool-round via the loop callbacks; OpenAI
members fall back to collected text at panel_member_done
- Frontend demuxes by member index into per-bubble interleaved text/tool
rendering
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Panel agents answer the user prompt in parallel (read-only, non-streaming);
their responses are merged into the worker's last user message as a
<panel_responses> block, and the session agent synthesizes one final
streamed answer. The RunPanel engine is built layer-ready for future MoA.
- New session fields: multi_model_mode (off/fusion), panel_agent_ids (CSV)
with idempotent column migration
- New partial Services/AnthropicService.Panel.cs holding the RunPanel engine
- Provider-agnostic members: Anthropic RunNonStreamingToolLoop / OpenAI
CompleteText / CLI plan-mode; all forced read-only, persisted with Tag=panel
- SSE events: panel_start, panel_member_start, panel_member_done, panel_done
- Frontend: multi-agent picker, live panel bubbles, history rendering
- Graceful degradation: panel errors fall back to worker-only
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
