diff --git a/docs/architecture.md b/docs/architecture.md
index 4780c4075..2d4995b3d 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -486,7 +486,9 @@ The central DB session row creation is the serialization point. No provider sess
 
 ### Output Delivery
 
-NanoClaw does not stream tokens to users. The provider's query interface yields complete results. The agent-runner writes one complete message to messages_out per result. The host delivers complete messages to channels.
+NanoClaw does not stream tokens to users. The provider's query interface yields complete results, but a result's text is not delivered as-is: the agent-runner parses it for `<message to="name">...</message>` blocks (`dispatchResultText` in poll-loop.ts) and writes one messages_out row per block, addressed to that destination with its thread context resolved per destination. Everything outside a block — including `<internal>...</internal>` — is scratchpad: logged, never sent. A block naming an unknown destination is dropped into the scratchpad log.
+
+If a result produced text but no valid block, the agent-runner pushes a one-time `<system>` nudge into the live turn asking the agent to re-wrap its response. The exception is a non-retryable error result (e.g. a billing error) with no envelope, which is delivered as an error notice instead of being dropped as scratchpad. Mid-turn interim updates go out through the `send_message` MCP tool; the final-text envelope parsing is how a turn's reply reaches the user. The host delivers complete messages_out rows to channels.
 
 Message editing is supported as an explicit operation (agent calls an `edit_message` tool), not as a streaming mechanism.