From e83d1957b44a31b2246b3a3207c029e368acd70d Mon Sep 17 00:00:00 2001
From: Alejandro Perez <alejandro.perez.gancedo@gmail.com>
Date: Fri, 3 Jul 2026 11:29:05 +0100
Subject: [PATCH] core+app: agent headline for board rows + resizable preview
 rail
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The table's agent's-read column showed a mid-sentence 2-line cut of the
intent paragraph — dense, not scannable. The pre-review contract now
asks for a dedicated one-line HEADLINE (<=80 chars) alongside the
intent; parse caps it at 120 and flattens whitespace; ingest stores it
on Review.distilled_headline (cleared with the other head-anchored
annotations). The table renders the headline (or the intent's first
sentence for pre-headline data) on a single line. Goldens regenerated
DELIBERATELY: the review output contract gained the headline field.

The preview rail is now resizable: drag its left divider (or arrow keys
when focused; double-click resets), width persisted and clamped to
300-720px.
---
 app/src-tauri/src/lib.rs                      |  5 +
 app/src/App.tsx                               | 97 +++++++++++++++++--
 app/src/bindings/Review.ts                    |  9 ++
 app/src/components/BoardTable.tsx             | 21 ++--
 app/src/lib/rail-width.test.ts                | 27 ++++++
 app/src/lib/rail-width.ts                     | 46 +++++++++
 app/src/lib/review-headline.test.ts           | 47 +++++++++
 app/src/lib/review-headline.ts                | 41 ++++++++
 app/src/test/fixtures.ts                      |  1 +
 crates/cockpit-core/src/adapters/github.rs    |  2 +
 crates/cockpit-core/src/findings.rs           | 60 +++++++++++-
 crates/cockpit-core/src/gate.rs               |  1 +
 crates/cockpit-core/src/kickoff.rs            |  3 +
 crates/cockpit-core/src/model.rs              |  9 ++
 crates/cockpit-core/src/persist.rs            |  1 +
 crates/cockpit-core/src/prompt.rs             |  4 +-
 crates/cockpit-core/src/restack.rs            |  1 +
 crates/cockpit-core/src/store.rs              |  1 +
 .../cockpit-core/tests/batch_fan_out_e2e.rs   |  1 +
 crates/cockpit-core/tests/e2e_round_trip.rs   |  1 +
 crates/cockpit-core/tests/fix_loop_e2e.rs     |  1 +
 .../tests/golden/review_prompt.txt            |  4 +-
 .../tests/golden/review_prompt_panel.txt      |  4 +-
 .../tests/golden/review_prompt_recap.txt      |  4 +-
 24 files changed, 363 insertions(+), 28 deletions(-)
 create mode 100644 app/src/lib/rail-width.test.ts
 create mode 100644 app/src/lib/rail-width.ts
 create mode 100644 app/src/lib/review-headline.test.ts
 create mode 100644 app/src/lib/review-headline.ts

diff --git a/app/src-tauri/src/lib.rs b/app/src-tauri/src/lib.rs
index 4f93468..92bc8dd 100644
--- a/app/src-tauri/src/lib.rs
+++ b/app/src-tauri/src/lib.rs
@@ -674,6 +674,9 @@ fn ingest_review_findings(state: &AppState, object_id: &str) -> &'static str {
             if let Some(intent) = review.intent {
                 r.distilled_intent = Some(intent);
             }
+            if let Some(headline) = review.headline {
+                r.distilled_headline = Some(headline);
+            }
         }
         if recap_present {
             r.recap_sha = Some(r.head_sha.clone());
@@ -788,6 +791,7 @@ async fn refresh_review_diff(state: &AppState, pr_ref: &PrRef) {
 fn clear_head_anchored_annotations(review: &mut Review) {
     review.review_findings.clear();
     review.distilled_intent = None;
+    review.distilled_headline = None;
 }
 
 /// Extract the PR number from a PR URL or reference string.
@@ -1420,6 +1424,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/app/src/App.tsx b/app/src/App.tsx
index d6a6d52..412be8e 100644
--- a/app/src/App.tsx
+++ b/app/src/App.tsx
@@ -52,6 +52,15 @@ import {
   saveDensity,
   WIDE_BREAKPOINT,
 } from "./lib/board-density";
+import {
+  clampRailWidth,
+  loadRailWidth,
+  saveRailWidth,
+  RAIL_DEFAULT_WIDTH,
+  RAIL_KEY_STEP,
+  RAIL_MIN_WIDTH,
+  RAIL_MAX_WIDTH,
+} from "./lib/rail-width";
 import type { GateState } from "./bindings/GateState";
 import type { DiffSide } from "./bindings/DiffSide";
 import type { Review } from "./bindings/Review";
@@ -301,6 +310,62 @@ function App() {
 
   // Triage-table selection (drives the preview rail), by PR ref.
   const [selectedPr, setSelectedPr] = useState<string | null>(null);
+
+  // User-resizable preview-rail width, persisted. Dragging tracks the pointer
+  // from a captured start position; the write happens once on release.
+  const [railWidth, setRailWidth] = useState<number>(loadRailWidth);
+  const railDrag = useRef<{ startX: number; startWidth: number } | null>(null);
+
+  const handleRailDragStart = useCallback(
+    (e: React.PointerEvent<HTMLDivElement>) => {
+      e.preventDefault();
+      e.currentTarget.setPointerCapture(e.pointerId);
+      railDrag.current = { startX: e.clientX, startWidth: railWidth };
+    },
+    [railWidth],
+  );
+  const handleRailDragMove = useCallback(
+    (e: React.PointerEvent<HTMLDivElement>) => {
+      const drag = railDrag.current;
+      if (drag === null) return;
+      // Dragging left widens the rail (the divider sits on its left edge).
+      setRailWidth(clampRailWidth(drag.startWidth + (drag.startX - e.clientX)));
+    },
+    [],
+  );
+  const handleRailDragEnd = useCallback(
+    (e: React.PointerEvent<HTMLDivElement>) => {
+      const drag = railDrag.current;
+      if (drag === null) return;
+      railDrag.current = null;
+      e.currentTarget.releasePointerCapture(e.pointerId);
+      saveRailWidth(clampRailWidth(drag.startWidth + (drag.startX - e.clientX)));
+    },
+    [],
+  );
+  const resetRailWidth = useCallback(() => {
+    setRailWidth(RAIL_DEFAULT_WIDTH);
+    saveRailWidth(RAIL_DEFAULT_WIDTH);
+  }, []);
+  const handleRailKeyDown = useCallback(
+    (e: React.KeyboardEvent<HTMLDivElement>) => {
+      // Left widens / right narrows, mirroring the drag direction.
+      const delta =
+        e.key === "ArrowLeft"
+          ? RAIL_KEY_STEP
+          : e.key === "ArrowRight"
+            ? -RAIL_KEY_STEP
+            : null;
+      if (delta === null) return;
+      e.preventDefault();
+      setRailWidth((w) => {
+        const next = clampRailWidth(w + delta);
+        saveRailWidth(next);
+        return next;
+      });
+    },
+    [],
+  );
   const requestDiffJump = useAppStore((s) => s.requestDiffJump);
   // Only render the preview rail when the window is wide enough for it.
   const railFits = useMediaQuery(RAIL_MIN_WIDTH_QUERY);
@@ -892,13 +957,33 @@ function App() {
             )}
           </div>
           {railFits && selectedReview !== null && (
-            <aside className="w-[380px] shrink-0 overflow-y-auto border-l border-border bg-card">
-              <BoardPreviewRail
-                review={selectedReview}
-                onOpen={handleOpenReview}
-                onJumpTo={handleRailJump}
+            <>
+              <div
+                role="separator"
+                aria-orientation="vertical"
+                aria-label="Resize preview rail"
+                aria-valuenow={railWidth}
+                aria-valuemin={RAIL_MIN_WIDTH}
+                aria-valuemax={RAIL_MAX_WIDTH}
+                tabIndex={0}
+                onPointerDown={handleRailDragStart}
+                onPointerMove={handleRailDragMove}
+                onPointerUp={handleRailDragEnd}
+                onDoubleClick={resetRailWidth}
+                onKeyDown={handleRailKeyDown}
+                className="w-1.5 shrink-0 cursor-col-resize outline-none transition-colors hover:bg-primary/30 focus-visible:bg-primary/40"
               />
-            </aside>
+              <aside
+                style={{ width: railWidth }}
+                className="shrink-0 overflow-y-auto border-l border-border bg-card"
+              >
+                <BoardPreviewRail
+                  review={selectedReview}
+                  onOpen={handleOpenReview}
+                  onJumpTo={handleRailJump}
+                />
+              </aside>
+            </>
           )}
         </>
       );
diff --git a/app/src/bindings/Review.ts b/app/src/bindings/Review.ts
index 698a28a..b4fed4e 100644
--- a/app/src/bindings/Review.ts
+++ b/app/src/bindings/Review.ts
@@ -146,6 +146,15 @@ last_reviewed_sha: string | null,
  * legacy data.
  */
 distilled_intent: string | null, 
+/**
+ * The pre-review agent's one-line (≤120 chars) summary of what the PR
+ * does, for card and table-row display where a paragraph doesn't scan.
+ *
+ * Same lifecycle as [`Self::distilled_intent`]: advisory display only,
+ * cleared when the head moves, `None` before the first pre-pass and for
+ * legacy data (display falls back to the intent's first sentence).
+ */
+distilled_headline: string | null, 
 /**
  * The head SHA the rendered pre-review recap was generated at, for
  * staleness. `None` before any recap and for legacy data.
diff --git a/app/src/components/BoardTable.tsx b/app/src/components/BoardTable.tsx
index cd81312..c51e680 100644
--- a/app/src/components/BoardTable.tsx
+++ b/app/src/components/BoardTable.tsx
@@ -23,7 +23,7 @@ import { StatusLed } from "./StatusLed";
 import { cardSignal, toneTextClass } from "../lib/card-signal";
 import { actionConfigForState } from "../lib/review-action";
 import { parsePrDisplay } from "../lib/pr-ref";
-import { stripMarkdown } from "../lib/markdown-text";
+import { reviewHeadline } from "../lib/review-headline";
 import { findingCounts, severityMeta } from "../lib/finding-severity";
 import { ciState } from "../lib/ci";
 import { diffTotals, sizeClass, sizeClassLabel } from "../lib/diff-signals";
@@ -163,13 +163,10 @@ function BoardRow({
   const signal = cardSignal(review);
   const action = actionConfigForState(review.gate_state);
   const { number: prNumber } = parsePrDisplay(review.pr);
-  const intent = useMemo(
-    () =>
-      review.distilled_intent !== null
-        ? stripMarkdown(review.distilled_intent)
-        : null,
-    [review.distilled_intent],
-  );
+  // One scannable line, not a mid-cut paragraph: the agent's dedicated
+  // headline, or the intent's first sentence for pre-headline data. The full
+  // read lives in the preview rail and the Briefing.
+  const headline = useMemo(() => reviewHeadline(review), [review]);
 
   return (
     <div
@@ -212,12 +209,12 @@ function BoardRow({
       </div>
 
       {/* Agent's read */}
-      {intent !== null ? (
+      {headline !== null ? (
         <p
-          className="line-clamp-2 text-xs leading-snug text-muted-foreground"
-          title={intent}
+          className="truncate text-xs leading-snug text-muted-foreground"
+          title={headline}
         >
-          {intent}
+          {headline}
         </p>
       ) : (
         <span className="text-xs text-muted-foreground/50" aria-hidden="true">
diff --git a/app/src/lib/rail-width.test.ts b/app/src/lib/rail-width.test.ts
new file mode 100644
index 0000000..108787a
--- /dev/null
+++ b/app/src/lib/rail-width.test.ts
@@ -0,0 +1,27 @@
+import { describe, it, expect } from "vitest";
+import {
+  clampRailWidth,
+  initialRailWidth,
+  RAIL_DEFAULT_WIDTH,
+  RAIL_MAX_WIDTH,
+  RAIL_MIN_WIDTH,
+} from "./rail-width";
+
+describe("clampRailWidth", () => {
+  it("clamps into the usable band and rounds", () => {
+    expect(clampRailWidth(100)).toBe(RAIL_MIN_WIDTH);
+    expect(clampRailWidth(10_000)).toBe(RAIL_MAX_WIDTH);
+    expect(clampRailWidth(400.6)).toBe(401);
+    expect(clampRailWidth(Number.NaN)).toBe(RAIL_DEFAULT_WIDTH);
+  });
+});
+
+describe("initialRailWidth", () => {
+  it("defaults when nothing or garbage is stored, clamps stored values", () => {
+    expect(initialRailWidth(null)).toBe(RAIL_DEFAULT_WIDTH);
+    expect(initialRailWidth("bogus")).toBe(RAIL_DEFAULT_WIDTH);
+    expect(initialRailWidth("500")).toBe(500);
+    expect(initialRailWidth("50")).toBe(RAIL_MIN_WIDTH);
+    expect(initialRailWidth("9999")).toBe(RAIL_MAX_WIDTH);
+  });
+});
diff --git a/app/src/lib/rail-width.ts b/app/src/lib/rail-width.ts
new file mode 100644
index 0000000..406df05
--- /dev/null
+++ b/app/src/lib/rail-width.ts
@@ -0,0 +1,46 @@
+/**
+ * Width model + persistence for the board's briefing preview rail.
+ *
+ * The rail is user-resizable by dragging its left edge (or arrow keys on the
+ * focused divider). The chosen width persists; malformed or out-of-range
+ * stored values clamp back into the usable band so a bad write can never
+ * produce an invisible or page-eating rail.
+ */
+
+/** localStorage key the persisted rail width (px) is stored under. */
+export const RAIL_WIDTH_KEY = "cockpit.board.railWidth";
+
+/** Narrowest useful rail: below this the findings rows wrap unreadably. */
+export const RAIL_MIN_WIDTH = 300;
+
+/** Widest allowed rail: keeps the triage table usable beside it. */
+export const RAIL_MAX_WIDTH = 720;
+
+/** Width before the user ever resizes (the D1 mockup's proportion). */
+export const RAIL_DEFAULT_WIDTH = 380;
+
+/** Step (px) for one arrow-key press on the focused resize divider. */
+export const RAIL_KEY_STEP = 16;
+
+/** Clamp any candidate width into the usable band. */
+export function clampRailWidth(width: number): number {
+  if (Number.isNaN(width)) return RAIL_DEFAULT_WIDTH;
+  return Math.min(RAIL_MAX_WIDTH, Math.max(RAIL_MIN_WIDTH, Math.round(width)));
+}
+
+/** Parse a stored raw value into a usable width, defaulting when malformed. */
+export function initialRailWidth(stored: string | null): number {
+  if (stored === null) return RAIL_DEFAULT_WIDTH;
+  const parsed = Number.parseInt(stored, 10);
+  return Number.isNaN(parsed) ? RAIL_DEFAULT_WIDTH : clampRailWidth(parsed);
+}
+
+/** Read the persisted rail width from `localStorage`. */
+export function loadRailWidth(): number {
+  return initialRailWidth(localStorage.getItem(RAIL_WIDTH_KEY));
+}
+
+/** Persist the user's rail width. */
+export function saveRailWidth(width: number): void {
+  localStorage.setItem(RAIL_WIDTH_KEY, String(clampRailWidth(width)));
+}
diff --git a/app/src/lib/review-headline.test.ts b/app/src/lib/review-headline.test.ts
new file mode 100644
index 0000000..e59e361
--- /dev/null
+++ b/app/src/lib/review-headline.test.ts
@@ -0,0 +1,47 @@
+import { describe, it, expect } from "vitest";
+import { reviewHeadline } from "./review-headline";
+import { makeReview } from "../test/fixtures";
+
+describe("reviewHeadline", () => {
+  it("prefers the agent-authored headline verbatim", () => {
+    const review = {
+      ...makeReview(),
+      distilled_headline: "Adds share-by-email behind a flag",
+      distilled_intent: "A long paragraph. With more sentences.",
+    };
+    expect(reviewHeadline(review)).toBe("Adds share-by-email behind a flag");
+  });
+
+  it("falls back to the intent's first sentence for pre-headline data", () => {
+    const review = {
+      ...makeReview(),
+      distilled_headline: null,
+      distilled_intent:
+        "Implements the Share flow for NEX-1605: a new QuoteEmailService renders and sends. A new table links emails to quotes.",
+    };
+    expect(reviewHeadline(review)).toBe(
+      "Implements the Share flow for NEX-1605: a new QuoteEmailService renders and sends.",
+    );
+  });
+
+  it("caps a boundary-free fallback with an ellipsis", () => {
+    const review = {
+      ...makeReview(),
+      distilled_headline: null,
+      distilled_intent: "x".repeat(400),
+    };
+    const headline = reviewHeadline(review);
+    expect(headline).not.toBeNull();
+    expect(headline?.length).toBe(160);
+    expect(headline?.endsWith("…")).toBe(true);
+  });
+
+  it("returns null when the review has no agent read", () => {
+    const review = {
+      ...makeReview(),
+      distilled_headline: null,
+      distilled_intent: null,
+    };
+    expect(reviewHeadline(review)).toBeNull();
+  });
+});
diff --git a/app/src/lib/review-headline.ts b/app/src/lib/review-headline.ts
new file mode 100644
index 0000000..3f88574
--- /dev/null
+++ b/app/src/lib/review-headline.ts
@@ -0,0 +1,41 @@
+import type { Review } from "../bindings/Review";
+import { stripMarkdown } from "./markdown-text";
+
+/**
+ * Longest fallback headline derived from the intent paragraph. The agent's own
+ * headline is capped harder (≤120) by the backend; this only bounds the
+ * first-sentence fallback for pre-headline data.
+ */
+const MAX_FALLBACK_CHARS = 160;
+
+/**
+ * The one-line summary of a review for cards and table rows.
+ *
+ * Prefers the agent-authored `distilled_headline` (a deliberate ≤80-char
+ * sentence from the pre-review contract). For reviews analyzed before the
+ * headline existed, falls back to the first sentence of the distilled intent —
+ * a mid-paragraph ellipsis cut is exactly what made the table column hard to
+ * scan. Returns null when the review has no agent read at all.
+ */
+export function reviewHeadline(review: Review): string | null {
+  if (review.distilled_headline !== null) return review.distilled_headline;
+  if (review.distilled_intent === null) return null;
+  const plain = stripMarkdown(review.distilled_intent).trim();
+  if (plain === "") return null;
+  return truncate(firstSentence(plain), MAX_FALLBACK_CHARS);
+}
+
+/**
+ * The first sentence of a paragraph: up to the first `.`, `!`, or `?` that is
+ * followed by whitespace or the end. Falls back to the whole text when no
+ * sentence boundary exists.
+ */
+function firstSentence(text: string): string {
+  const match = /^[\s\S]*?[.!?](?=\s|$)/.exec(text);
+  return (match?.[0] ?? text).trim();
+}
+
+/** Hard char cap with a single-character ellipsis. */
+function truncate(text: string, max: number): string {
+  return text.length <= max ? text : `${text.slice(0, max - 1).trimEnd()}…`;
+}
diff --git a/app/src/test/fixtures.ts b/app/src/test/fixtures.ts
index 9366b1a..db1abc7 100644
--- a/app/src/test/fixtures.ts
+++ b/app/src/test/fixtures.ts
@@ -60,6 +60,7 @@ export function makeReview(overrides: Partial<Review> = {}): Review {
     ci_summary: null,
     last_reviewed_sha: null,
     distilled_intent: null,
+    distilled_headline: null,
     recap_sha: null,
   };
   return { ...base, ...overrides };
diff --git a/crates/cockpit-core/src/adapters/github.rs b/crates/cockpit-core/src/adapters/github.rs
index 167c1ad..9704dae 100644
--- a/crates/cockpit-core/src/adapters/github.rs
+++ b/crates/cockpit-core/src/adapters/github.rs
@@ -944,6 +944,7 @@ pub fn build_review_from_pr(
         conversation: vec![],
         last_reviewed_sha: None,
         distilled_intent: None,
+        distilled_headline: None,
         recap_sha: None,
     }
 }
@@ -2665,6 +2666,7 @@ index 1111111..2222222 100644
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/src/findings.rs b/crates/cockpit-core/src/findings.rs
index 1557c88..9eeb977 100644
--- a/crates/cockpit-core/src/findings.rs
+++ b/crates/cockpit-core/src/findings.rs
@@ -51,6 +51,12 @@ const MAX_INTENT_CHARS: usize = 2000;
 /// is truncated on a `char` boundary.
 const MAX_AREA_CHARS: usize = 32;
 
+/// Upper bound on the character length of a distilled headline.
+///
+/// The prompt asks for at most 80 characters; the cap allows some slack while
+/// keeping the value a single scannable line for cards and table rows.
+const MAX_HEADLINE_CHARS: usize = 120;
+
 /// Errors from parsing reviewer output.
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
@@ -71,6 +77,9 @@ pub struct ParsedReview {
     /// The reviewer's distilled read of what the PR does, capped at
     /// [`MAX_INTENT_CHARS`]. `None` when absent (legacy array) or empty.
     pub intent: Option<String>,
+    /// One-line summary of what the PR does, whitespace-flattened and capped
+    /// at [`MAX_HEADLINE_CHARS`]. `None` when absent or empty.
+    pub headline: Option<String>,
     /// The advisory findings, at most [`MAX_FINDINGS`] of them.
     pub findings: Vec<ReviewFinding>,
 }
@@ -117,18 +126,27 @@ pub fn parse_review_output(text: &str) -> Result<ParsedReview, Error> {
             .get("intent")
             .and_then(Value::as_str)
             .and_then(cap_intent);
+        let headline = obj
+            .get("headline")
+            .and_then(Value::as_str)
+            .and_then(cap_headline);
         let findings = obj
             .get("findings")
             .and_then(Value::as_array)
             .map(|array| build_findings(array))
             .unwrap_or_default();
-        return Ok(ParsedReview { intent, findings });
+        return Ok(ParsedReview {
+            intent,
+            headline,
+            findings,
+        });
     }
 
-    // Legacy bare array: no intent.
+    // Legacy bare array: no intent, no headline.
     let array = extract_findings_array(text).ok_or(Error::NoArrayFound)?;
     Ok(ParsedReview {
         intent: None,
+        headline: None,
         findings: build_findings(&array),
     })
 }
@@ -176,6 +194,21 @@ fn cap_intent(raw: &str) -> Option<String> {
     Some(capped.to_owned())
 }
 
+/// Trim, whitespace-flatten, and cap a raw headline, returning `None` when it
+/// is empty. Newlines collapse to single spaces so the value is always one
+/// line, whatever the agent wrote.
+fn cap_headline(raw: &str) -> Option<String> {
+    let flattened = raw.split_whitespace().collect::<Vec<_>>().join(" ");
+    if flattened.is_empty() {
+        return None;
+    }
+    let capped = match flattened.char_indices().nth(MAX_HEADLINE_CHARS) {
+        Some((idx, _)) => flattened[..idx].to_owned(),
+        None => flattened,
+    };
+    Some(capped)
+}
+
 /// Extract the first brace region that parses as the v2 review object.
 ///
 /// Scans for each `{` and, using a string-aware balanced walk
@@ -581,11 +614,34 @@ mod tests {
         let json = r#"[{"severity":"Info","path":"a.rs","line_start":1,"line_end":1,"title":"t","rationale":"r"}]"#;
         let parsed = parse_review_output(json).expect("legacy array should parse");
         assert_eq!(parsed.intent, None);
+        assert_eq!(parsed.headline, None);
         assert_eq!(parsed.findings.len(), 1);
         // A legacy entry with no area normalizes to None.
         assert_eq!(parsed.findings[0].area, None);
     }
 
+    #[test]
+    fn headline_is_flattened_capped_and_optional() {
+        // Newlines flatten to single spaces: the headline is always one line.
+        let json = r#"{"intent":"i","headline":"Adds share\n  by email","findings":[]}"#;
+        let parsed = parse_review_output(json).expect("should parse");
+        assert_eq!(parsed.headline.as_deref(), Some("Adds share by email"));
+
+        // Over-long headlines cap at MAX_HEADLINE_CHARS on a char boundary.
+        let long = "x".repeat(500);
+        let json = format!(r#"{{"intent":"i","headline":"{long}","findings":[]}}"#);
+        let parsed = parse_review_output(&json).expect("should parse");
+        assert_eq!(
+            parsed.headline.map(|h| h.chars().count()),
+            Some(MAX_HEADLINE_CHARS)
+        );
+
+        // Absent or whitespace-only → None.
+        let json = r#"{"intent":"i","headline":"  ","findings":[]}"#;
+        let parsed = parse_review_output(json).expect("should parse");
+        assert_eq!(parsed.headline, None);
+    }
+
     #[test]
     fn intent_is_capped() {
         let long_intent = "x".repeat(MAX_INTENT_CHARS + 500);
diff --git a/crates/cockpit-core/src/gate.rs b/crates/cockpit-core/src/gate.rs
index 09d8605..a8c3f4a 100644
--- a/crates/cockpit-core/src/gate.rs
+++ b/crates/cockpit-core/src/gate.rs
@@ -340,6 +340,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/src/kickoff.rs b/crates/cockpit-core/src/kickoff.rs
index f2ebf47..b699a67 100644
--- a/crates/cockpit-core/src/kickoff.rs
+++ b/crates/cockpit-core/src/kickoff.rs
@@ -206,6 +206,7 @@ fn build_review(
         conversation: vec![],
         last_reviewed_sha: None,
         distilled_intent: None,
+        distilled_headline: None,
         recap_sha: None,
     }
 }
@@ -838,6 +839,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }];
 
@@ -874,6 +876,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         };
 
diff --git a/crates/cockpit-core/src/model.rs b/crates/cockpit-core/src/model.rs
index a55d8a5..49e32c3 100644
--- a/crates/cockpit-core/src/model.rs
+++ b/crates/cockpit-core/src/model.rs
@@ -568,6 +568,14 @@ pub struct Review {
     /// legacy data.
     #[serde(default)]
     pub distilled_intent: Option<String>,
+    /// The pre-review agent's one-line (≤120 chars) summary of what the PR
+    /// does, for card and table-row display where a paragraph doesn't scan.
+    ///
+    /// Same lifecycle as [`Self::distilled_intent`]: advisory display only,
+    /// cleared when the head moves, `None` before the first pre-pass and for
+    /// legacy data (display falls back to the intent's first sentence).
+    #[serde(default)]
+    pub distilled_headline: Option<String>,
     /// The head SHA the rendered pre-review recap was generated at, for
     /// staleness. `None` before any recap and for legacy data.
     ///
@@ -617,6 +625,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/src/persist.rs b/crates/cockpit-core/src/persist.rs
index 3baf3ee..8c750db 100644
--- a/crates/cockpit-core/src/persist.rs
+++ b/crates/cockpit-core/src/persist.rs
@@ -154,6 +154,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/src/prompt.rs b/crates/cockpit-core/src/prompt.rs
index c1e80d7..83a79b1 100644
--- a/crates/cockpit-core/src/prompt.rs
+++ b/crates/cockpit-core/src/prompt.rs
@@ -70,7 +70,7 @@ If a conflict is ambiguous, stop and say so.";
 /// (see [`render_review_instruction`]).
 const REVIEW_HEAD: &str = "Act as a read-only advisory reviewer for the pull request above. Work in three steps.
 
-1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes.";
+1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes. Also write a HEADLINE: one plain sentence of at most 80 characters naming what the PR does, no markdown, no trailing period.";
 
 /// Step 2 for the single-pass variant (no lenses): one general review with NO
 /// subagent mention at all, so a small/medium diff never fans out.
@@ -86,7 +86,7 @@ const REVIEW_BUDGET: &str = "Review the DIFF, not the repository. Read only file
 /// JSON output contract and the advisory-only constraint). Identical across both
 /// variants. The output object is parsed by [`crate::findings::parse_review_output`].
 const REVIEW_TAIL: &str = r#"3. Output ONE JSON OBJECT to the output path, and nothing else, in this shape:
-   {"intent":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
+   {"intent":"...","headline":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
    Set each finding's "area" to the lens that produced it. This pass is advisory only: do NOT edit any code."#;
 
 /// The default (single-pass) advisory-reviewer instruction.
diff --git a/crates/cockpit-core/src/restack.rs b/crates/cockpit-core/src/restack.rs
index c08e1bc..ac21154 100644
--- a/crates/cockpit-core/src/restack.rs
+++ b/crates/cockpit-core/src/restack.rs
@@ -322,6 +322,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/src/store.rs b/crates/cockpit-core/src/store.rs
index 8f97cbd..1d2edea 100644
--- a/crates/cockpit-core/src/store.rs
+++ b/crates/cockpit-core/src/store.rs
@@ -421,6 +421,7 @@ mod tests {
             conversation: vec![],
             last_reviewed_sha: None,
             distilled_intent: None,
+            distilled_headline: None,
             recap_sha: None,
         }
     }
diff --git a/crates/cockpit-core/tests/batch_fan_out_e2e.rs b/crates/cockpit-core/tests/batch_fan_out_e2e.rs
index adae815..6e5e0c7 100644
--- a/crates/cockpit-core/tests/batch_fan_out_e2e.rs
+++ b/crates/cockpit-core/tests/batch_fan_out_e2e.rs
@@ -146,6 +146,7 @@ fn make_review(id: &str, branch: &str, worktree: PathBuf, project: &ProjectId) -
         conversation: vec![],
         last_reviewed_sha: None,
         distilled_intent: None,
+        distilled_headline: None,
         recap_sha: None,
     }
 }
diff --git a/crates/cockpit-core/tests/e2e_round_trip.rs b/crates/cockpit-core/tests/e2e_round_trip.rs
index f319408..0eacc23 100644
--- a/crates/cockpit-core/tests/e2e_round_trip.rs
+++ b/crates/cockpit-core/tests/e2e_round_trip.rs
@@ -47,6 +47,7 @@ fn make_test_review(worktree: PathBuf) -> Review {
         conversation: vec![],
         last_reviewed_sha: None,
         distilled_intent: None,
+        distilled_headline: None,
         recap_sha: None,
     }
 }
diff --git a/crates/cockpit-core/tests/fix_loop_e2e.rs b/crates/cockpit-core/tests/fix_loop_e2e.rs
index 6e1a534..2732a77 100644
--- a/crates/cockpit-core/tests/fix_loop_e2e.rs
+++ b/crates/cockpit-core/tests/fix_loop_e2e.rs
@@ -176,6 +176,7 @@ fn make_review(worktree: PathBuf, branch: &str, head_sha: &str) -> Review {
         conversation: vec![],
         last_reviewed_sha: None,
         distilled_intent: None,
+        distilled_headline: None,
         recap_sha: None,
     }
 }
diff --git a/crates/cockpit-core/tests/golden/review_prompt.txt b/crates/cockpit-core/tests/golden/review_prompt.txt
index 3cff9b2..0d08fcd 100644
--- a/crates/cockpit-core/tests/golden/review_prompt.txt
+++ b/crates/cockpit-core/tests/golden/review_prompt.txt
@@ -18,14 +18,14 @@ diff --git a/src/main.rs b/src/main.rs
 
 Act as a read-only advisory reviewer for the pull request above. Work in three steps.
 
-1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes.
+1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes. Also write a HEADLINE: one plain sentence of at most 80 characters naming what the PR does, no markdown, no trailing period.
 
 2. Review the DIFF against that intent in a single general pass, covering correctness, tests, and anything the change puts at risk.
 
 Review the DIFF, not the repository. Read only files in the diff plus directly referenced definitions. Budget: about 25 tool calls total (about 15 per subagent when spawned). Do not run builds or test suites. When verification would need a deep chain of reads, report the finding as a Warning with your assumption stated in the rationale instead of chasing it. Aim to complete within 5 minutes.
 
 3. Output ONE JSON OBJECT to the output path, and nothing else, in this shape:
-   {"intent":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
+   {"intent":"...","headline":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
    Set each finding's "area" to the lens that produced it. This pass is advisory only: do NOT edit any code.
 
 ## Output
diff --git a/crates/cockpit-core/tests/golden/review_prompt_panel.txt b/crates/cockpit-core/tests/golden/review_prompt_panel.txt
index 4357ab2..60940e1 100644
--- a/crates/cockpit-core/tests/golden/review_prompt_panel.txt
+++ b/crates/cockpit-core/tests/golden/review_prompt_panel.txt
@@ -18,14 +18,14 @@ diff --git a/src/main.rs b/src/main.rs
 
 Act as a read-only advisory reviewer for the pull request above. Work in three steps.
 
-1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes.
+1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes. Also write a HEADLINE: one plain sentence of at most 80 characters naming what the PR does, no markdown, no trailing period.
 
 2. Spawn AT MOST 2 parallel subagents with your Task tool, one per lens: security, frontend. Each subagent reviews ONLY its lens, then merge and de-duplicate their findings. Do not spawn more than 2 subagents.
 
 Review the DIFF, not the repository. Read only files in the diff plus directly referenced definitions. Budget: about 25 tool calls total (about 15 per subagent when spawned). Do not run builds or test suites. When verification would need a deep chain of reads, report the finding as a Warning with your assumption stated in the rationale instead of chasing it. Aim to complete within 5 minutes.
 
 3. Output ONE JSON OBJECT to the output path, and nothing else, in this shape:
-   {"intent":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
+   {"intent":"...","headline":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
    Set each finding's "area" to the lens that produced it. This pass is advisory only: do NOT edit any code.
 
 ## Output
diff --git a/crates/cockpit-core/tests/golden/review_prompt_recap.txt b/crates/cockpit-core/tests/golden/review_prompt_recap.txt
index 08e936e..cbe4f2f 100644
--- a/crates/cockpit-core/tests/golden/review_prompt_recap.txt
+++ b/crates/cockpit-core/tests/golden/review_prompt_recap.txt
@@ -18,14 +18,14 @@ diff --git a/src/main.rs b/src/main.rs
 
 Act as a read-only advisory reviewer for the pull request above. Work in three steps.
 
-1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes.
+1. Distill the INTENT. In 2-4 sentences, state what this PR actually does — judged from the title, body, and diff — and call out any gap between what it claims and what it changes. Also write a HEADLINE: one plain sentence of at most 80 characters naming what the PR does, no markdown, no trailing period.
 
 2. Review the DIFF against that intent in a single general pass, covering correctness, tests, and anything the change puts at risk.
 
 Review the DIFF, not the repository. Read only files in the diff plus directly referenced definitions. Budget: about 25 tool calls total (about 15 per subagent when spawned). Do not run builds or test suites. When verification would need a deep chain of reads, report the finding as a Warning with your assumption stated in the rationale instead of chasing it. Aim to complete within 5 minutes.
 
 3. Output ONE JSON OBJECT to the output path, and nothing else, in this shape:
-   {"intent":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
+   {"intent":"...","headline":"...","findings":[{"severity":"Info|Warning|Critical","path":"...","line_start":N,"line_end":N,"side":"Old|New","title":"...","rationale":"...","area":"frontend|backend|infra|security|general"}]}
    Set each finding's "area" to the lens that produced it. This pass is advisory only: do NOT edit any code.
 
 ## Output