From 30f45d6ec794ff2666cea9540d264a5c0a55da01 Mon Sep 17 00:00:00 2001
From: Shrinivas Biradar <ping.shrinivas@gmail.com>
Date: Mon, 25 May 2026 15:29:33 +0530
Subject: [PATCH 1/2] mergeTooShort() never merges a short first segment
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The function merges short segments into the preceding one using this guard:
if (result.length > 0 && part.length < MIN_SEGMENT_CHARS)
When the very first segment is short (e.g. "Ok."), result.length === 0, so it's pushed as-is. The second segment then passes the length check and gets pushed separately — leaving a tiny stub bubble as the first chat message.
Fix: After the main loop, if result[0] is still below the minimum, forward-merge it into result[1].
---
 app/src/utils/messageSegmentation.ts | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/app/src/utils/messageSegmentation.ts b/app/src/utils/messageSegmentation.ts
index baf33c450e..4a91af14ff 100644
--- a/app/src/utils/messageSegmentation.ts
+++ b/app/src/utils/messageSegmentation.ts
@@ -59,7 +59,18 @@ export function getSegmentDelay(segment: string): number {
 
 // ─── helpers ─────────────────────────────────────────────────────────────────
 
-/** Merge adjacent items that are shorter than MIN_SEGMENT_CHARS. */
+/**
+ * Merge adjacent items that are shorter than MIN_SEGMENT_CHARS.
+ *
+ * Previously only short segments following a prior segment were merged (into
+ * the preceding one). A short *first* segment was left as-is because the
+ * `result.length > 0` guard prevented it from being absorbed. This caused the
+ * first chat bubble to show fewer than MIN_SEGMENT_CHARS characters while all
+ * subsequent short segments were correctly consolidated.
+ *
+ * Fix: after the normal backward-merge pass, check whether the first segment
+ * is still too short and, if so, forward-merge it into the second segment.
+ */
 function mergeTooShort(parts: string[], joiner: string): string[] {
   const result: string[] = [];
   for (const part of parts) {
@@ -69,6 +80,14 @@ function mergeTooShort(parts: string[], joiner: string): string[] {
       result.push(part);
     }
   }
+
+  // If the first segment is still shorter than the minimum, forward-merge it
+  // into the second segment (if one exists) so no leading stub bubble is shown.
+  if (result.length >= 2 && result[0].length < MIN_SEGMENT_CHARS) {
+    result[1] = result[0] + joiner + result[1];
+    result.shift();
+  }
+
   return result;
 }
 

From 781bf66f4f3a17baec825eb3b91b437f69923a76 Mon Sep 17 00:00:00 2001
From: Steven Enamakel <enamakel@tinyhumans.ai>
Date: Thu, 28 May 2026 14:46:18 -0700
Subject: [PATCH 2/2] test(messageSegmentation): cover short first-segment
 forward-merge (addresses @coderabbitai)

---
 .../__tests__/messageSegmentation.test.ts     | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/app/src/utils/__tests__/messageSegmentation.test.ts b/app/src/utils/__tests__/messageSegmentation.test.ts
index d49236c23c..5f9ae92d75 100644
--- a/app/src/utils/__tests__/messageSegmentation.test.ts
+++ b/app/src/utils/__tests__/messageSegmentation.test.ts
@@ -33,6 +33,32 @@ describe('segmentMessage', () => {
     expect(segments.every(s => s.length >= 40)).toBe(true);
   });
 
+  it('merges a short first paragraph into the second paragraph', () => {
+    const text =
+      'Ok.\n\n' +
+      'This second paragraph is intentionally long enough to stand alone after merging.';
+    const segments = segmentMessage(text);
+
+    expect(segments.length).toBe(1);
+    expect(segments[0].startsWith('Ok.\n\n')).toBe(true);
+    expect(segments[0].length).toBeGreaterThanOrEqual(40);
+  });
+
+  it('forward-merges a short first paragraph yet keeps the remaining bubbles', () => {
+    // Three paragraphs where only the first is below MIN_SEGMENT_CHARS. This
+    // exercises the forward-merge branch in mergeTooShort while still returning
+    // multiple segments from the paragraph-split strategy (no leading stub).
+    const text =
+      'Ok.\n\n' +
+      'This second paragraph is intentionally long enough to stand alone as a bubble.\n\n' +
+      'And a third paragraph that is also long enough to remain its own standalone bubble.';
+    const segments = segmentMessage(text);
+
+    expect(segments).toHaveLength(2);
+    expect(segments[0].startsWith('Ok.\n\n')).toBe(true);
+    expect(segments.every(s => s.length >= 40)).toBe(true);
+  });
+
   it('splits on sentence boundaries when no paragraph breaks exist', () => {
     const text =
       'This is the first sentence with some content. This is the second sentence with more content. ' +