[alexwan02]

What

When a client does not advertise session.notices, a notice falls back to an agent_message_chunk like **Notice:** …. Clients render consecutive chunks as one markdown stream, so the fallback is glued to Claude's last sentence. In Zed 1.24 a Stop hook's systemMessage shows up as:

…推上去。**Notice:** Stop says: token: 3 calls
Stop says: hand off now

The fallback is now its own blockquote paragraph, with blank lines on both sides:

…推上去。

> **Notice:** Stop says: token: 3 calls
> hand off now

Behavior

• noticeOrTranscriptUpdate wraps the transcript text with transcriptBlock: a leading blank line so it starts on a new line, > on every line, and a trailing blank line so Claude's next chunk does not continue the quote. This covers every transcript fallback (hook notices, "Task stopped by user", "Fast mode turned off", "Auto mode unavailable").
• Claude Code prefixes every line of a hook's systemMessage with <HookEvent> says: . The informational fallback keeps that prefix on the first line only, and only when every line repeats the same prefix (collapseHookSpeaker).
• Clients that advertise session.notices get the same notice update as before.
• Turn.noticeTexts still records message.content unchanged, so the hook-blocked result de-duplication keeps working.

Tests

• New unit tests for transcriptBlock and collapseHookSpeaker, plus an end-to-end test for a two-line notice-level hook message.
• Updated the existing transcript fallback assertions to the blockquote form.
• npm run check, npm run build and npm run test:run pass (3111 tests).