From d37e1d3dc3ceef72c0bd74dbd55c86f0fb9eefcc Mon Sep 17 00:00:00 2001
From: Dotta <bippadotta@protonmail.com>
Date: Thu, 5 Mar 2026 09:25:03 -0600
Subject: [PATCH] preserve thinking delta whitespace in runlog streaming

---
 packages/adapters/cursor-local/src/ui/parse-stdout.ts |  8 +++++---
 server/src/__tests__/cursor-local-adapter.test.ts     | 11 +++++++++++
 ui/src/components/ActiveAgentsPanel.tsx               |  4 ++--
 ui/src/components/LiveRunWidget.tsx                   |  4 ++--
 4 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/packages/adapters/cursor-local/src/ui/parse-stdout.ts b/packages/adapters/cursor-local/src/ui/parse-stdout.ts
index 9690b507..047a9041 100644
--- a/packages/adapters/cursor-local/src/ui/parse-stdout.ts
+++ b/packages/adapters/cursor-local/src/ui/parse-stdout.ts
@@ -218,11 +218,13 @@ export function parseCursorStdoutLine(line: string, ts: string): TranscriptEntry
   }
 
   if (type === "thinking") {
-    const text = asString(parsed.text).trim() || asString(asRecord(parsed.delta)?.text).trim();
+    const textFromTopLevel = asString(parsed.text);
+    const textFromDelta = asString(asRecord(parsed.delta)?.text);
+    const text = textFromTopLevel.length > 0 ? textFromTopLevel : textFromDelta;
     const subtype = asString(parsed.subtype).trim().toLowerCase();
     const isDelta = subtype === "delta" || asRecord(parsed.delta) !== null;
-    if (!text) return [];
-    return [{ kind: "thinking", ts, text, ...(isDelta ? { delta: true } : {}) }];
+    if (!text.trim()) return [];
+    return [{ kind: "thinking", ts, text: isDelta ? text : text.trim(), ...(isDelta ? { delta: true } : {}) }];
   }
 
   if (type === "tool_call") {
diff --git a/server/src/__tests__/cursor-local-adapter.test.ts b/server/src/__tests__/cursor-local-adapter.test.ts
index aad83bc7..22bb4ba6 100644
--- a/server/src/__tests__/cursor-local-adapter.test.ts
+++ b/server/src/__tests__/cursor-local-adapter.test.ts
@@ -164,6 +164,17 @@ describe("cursor ui stdout parser", () => {
       ),
     ).toEqual([{ kind: "thinking", ts, text: "planning next command", delta: true }]);
 
+    expect(
+      parseCursorStdoutLine(
+        JSON.stringify({
+          type: "thinking",
+          subtype: "delta",
+          text: " with preserved leading space",
+        }),
+        ts,
+      ),
+    ).toEqual([{ kind: "thinking", ts, text: " with preserved leading space", delta: true }]);
+
     expect(
       parseCursorStdoutLine(
         JSON.stringify({
diff --git a/ui/src/components/ActiveAgentsPanel.tsx b/ui/src/components/ActiveAgentsPanel.tsx
index 53a1af9f..d9db179d 100644
--- a/ui/src/components/ActiveAgentsPanel.tsx
+++ b/ui/src/components/ActiveAgentsPanel.tsx
@@ -100,8 +100,8 @@ function parseStdoutChunk(
   const summarized: Array<{ text: string; tone: FeedTone; thinkingDelta?: boolean }> = [];
   const appendSummary = (entry: TranscriptEntry) => {
     if (entry.kind === "thinking" && entry.delta) {
-      const text = entry.text.trim();
-      if (!text) return;
+      const text = entry.text;
+      if (!text.trim()) return;
       const last = summarized[summarized.length - 1];
       if (last && last.thinkingDelta) {
         last.text += text;
diff --git a/ui/src/components/LiveRunWidget.tsx b/ui/src/components/LiveRunWidget.tsx
index 0febefd4..253152d0 100644
--- a/ui/src/components/LiveRunWidget.tsx
+++ b/ui/src/components/LiveRunWidget.tsx
@@ -111,8 +111,8 @@ function parseStdoutChunk(
   const summarized: Array<{ text: string; tone: FeedTone; thinkingDelta?: boolean }> = [];
   const appendSummary = (entry: TranscriptEntry) => {
     if (entry.kind === "thinking" && entry.delta) {
-      const text = entry.text.trim();
-      if (!text) return;
+      const text = entry.text;
+      if (!text.trim()) return;
       const last = summarized[summarized.length - 1];
       if (last && last.thinkingDelta) {
         last.text += text;