[tdody]

Summary

Fixes THI-416. A "{pane} is done" banner's body was a line read off the pane's screen (w.last_line), and on live panes that line was rarely the reply. In prod's /api/state it was usually one of these:

• the turn-timing line: ✻ Brewed for 42s · done 1:27 PM;
• a ⎿ line: ⎿ Allowed by auto mode classifier, ⎿ Tip: …;
• the right-aligned new task? /clear to save 433.4k tokens hint above the composer;
• for a named session, the footer: the custom statusline and the ⧉ row. Claude prints the session name in the composer's top rule (──── name ─). DIALOG_RULE_RE doesn't match a labeled rule, so the composer went undetected and THI-434's footer cut never applied.

The reply, from the transcript (turns.py, window_view.py)

• For a done Claude pane, /api/state now carries last_reply. turns.last_reply_for_session reads the session's JSONL backward from the end to the newest assistant text.
  • Bookkeeping rows are skipped: turn_duration, artifact-autoreact-ledger, mode, and meta and sidechain events.
  • It returns None once a prompt follows that text, so a new turn never shows the previous reply.
  • Markdown is flattened (links to their text, no ** or backticks, no headings or code blocks) and the result capped at 400 characters.
• Cost: under 1 ms uncached on live transcripts (2–54 MB). Results are cached per session on the file's size and mtime, so a done pane costs one stat per poll. Working panes aren't read.
• There's no newest-mtime-in-cwd fallback: a wrong transcript would put another pane's words in the banner.

Banner (notify/copy.js): last_reply, then recap, then last_line, then "Finished.".

Screen fallback (panes.py), for when no transcript is found:

• _composer_rows accepts a named top rule (_COMPOSER_TOP_RE). The lower rule and a dialog's rule must still be plain.
• _last_meaningful_line returns the start of the newest reply on screen: its ⏺ row plus the wrapped rows under it, up to the first blank row. Its last row had read as half a sentence; a banner said "that use it would fail.". It returns "" when the newest ⏺ is a tool call, including collapsed groups and MCP calls, so the banner says "Finished." instead of a tool header. With no ⏺ on screen, it falls back to the closest line that isn't chrome or the turn's own (✻, ⎿, rows indented 20+ columns). All of this is local to it, so _detect_asked_question reads the same lines as before.
• This matters beyond panes without a transcript. After a server update, an open page runs the old notification code (recap || last_line) until it's reloaded, and that's the code that produced the half-sentence banner on this machine.
• _split_buffers strips every escape (_strip_escapes), OSC 8 hyperlinks included, not just SGR.

Docs: docs/channels.md (how last_reply is read), invariant 2 (the named rule), and the done row of the native-notifications spec.

Worth a look in review

The named-rule fix also changes Reply on named sessions. composer_ready used to find no composer there, so a banner's Reply always got a 409. Now it can type the reply. Every other check is unchanged:

• one ❯ row, empty or a ghost suggestion;
• no dialog above;
• composer_holds before Enter.

A typed draft under a named rule is still refused (tested). If you'd rather keep Reply off for named sessions, the change is limited to _composer_rows.

Test plan

• uv run pytest -q: 2027 passed. New:
  • test_turns.py: the reply under bookkeeping, a notification turn, None after a prompt, meta and sidechain skipped, the markdown flattening, the cap, a read past one chunk, giving up past the reach, a torn row, and the per-session cache.
  • test_window_view.py: last_reply published for a done pane only.
  • test_panes.py:
    • last_line cases for a named session's footer with an OSC 8 link, a ⎿ tip under the reply, the /clear hint, the start of a multi-paragraph reply rather than its last row, and turns that ended in a tool or MCP call;
    • a named session's composer is detected and composer_ready;
    • the three cases that expected ✻ Brewed for … now expect the reply line above it.
• npx vitest run: 1299 passed, including the done body's priority (last_reply > recap > last_line > "Finished.").
• bin/check: passes (3 pre-existing biome warnings in files this PR doesn't touch).
• static/dist rebuilt.
• Dev server (:17375) on live panes:
  • both done panes' banner bodies were their real first sentence, e.g. "I pushed 6caa5f4b35 to #7574, covering 12 of Brendan's 18 comments.", built by running payloadFor over the live /api/state;
  • every idle pane's last_line was the start of its newest reply, including the named session and the one under the /clear hint.
• A real macOS banner after deploy.

🤖 Generated with Claude Code