Suppress interim text echoes in Thinking cards

CHANGELOG.md

@@ -8,6 +8,8 @@
 
 ### Fixed
 
+- **PR TBD** by @franksong2702 — Thinking cards now suppress exact snippets that are already shown as user-visible interim assistant text, avoiding duplicated progress lines when an agent emits the same sentence through both reasoning and interim-assistant callbacks.
+
 - **PR #2322** by @Michaelyklam (refs #2271) — LAN Ollama models selected from endpoint-discovered `custom:<host>-<port>` / `custom:<host>:<port>` picker entries now route through the configured `ollama` provider and base URL instead of surfacing a missing `CUSTOM_*_API_KEY` error. The picker still surfaces endpoint-discovered entries; the fix is to recognize them as UI routing hints matching the configured local-server base URL and resolve them via the actual `ollama` provider.
 
 

static/messages.js

@@ -432,6 +432,7 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
   let assistantText='';
   let reasoningText='';
   let liveReasoningText='';
+  let visibleInterimSnippets=[];
   let _latestGoalStatus=null;
   let _pendingGoalContinuation=null;
   let assistantRow=null;
@@ -527,6 +528,19 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
   function _closeSource(){
     closeLiveStream(activeSid, streamId);
   }
+  function _stripLiveVisibleAssistantEchoFromThinking(text, snippets){
+    let out=String(text||'');
+    (Array.isArray(snippets)?snippets:[]).forEach(snippet=>{
+      const visible=String(snippet||'').trim();
+      if(visible.length<20) return;
+      out=out.split(visible).join('');
+    });
+    return out.trim();
+  }
+  function _liveThinkingText(){
+    const clean=_stripLiveVisibleAssistantEchoFromThinking(liveReasoningText, visibleInterimSnippets);
+    return clean || 'Thinking…';
+  }
   function syncInflightAssistantMessage(){
     const inflight=INFLIGHT[activeSid];
     if(!inflight) return;
@@ -1190,9 +1204,14 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
         return;
       }
       assistantText+=visible;
+      visibleInterimSnippets.push(visible);
       syncInflightAssistantMessage();
       if(!S.session||S.session.session_id!==activeSid) return;
       const parsed=_parseStreamState();
+      if(window._showThinking!==false){
+        if(typeof updateThinking==='function') updateThinking(_liveThinkingText());
+        else appendThinking(_liveThinkingText());
+      }
       if(String((parsed&&parsed.displayText)||'').trim()||assistantRow) ensureAssistantRow();
       _scheduleRender();
     });
@@ -1209,8 +1228,8 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
       // finalizeThinkingCard(). The old rAF-only path caused a race where
       // the thinking row was still a spinner when finalized.
       if(window._showThinking!==false){
-        if(typeof updateThinking==='function') updateThinking(liveReasoningText||'Thinking…');
-        else appendThinking(liveReasoningText);
+        if(typeof updateThinking==='function') updateThinking(_liveThinkingText());
+        else appendThinking(_liveThinkingText());
       }
       _scheduleRender();
     });

static/ui.js

@@ -2308,6 +2308,16 @@ function _sanitizeThinkingDisplayText(text){
   return stripped.trim();
 }
 
+function _stripVisibleAssistantEchoFromThinking(thinkingText, visibleText){
+  let out=String(thinkingText||'');
+  const visible=String(visibleText||'');
+  if(!out||!visible) return out.trim();
+  visible.split(/\n{2,}/).map(s=>s.trim()).filter(s=>s.length>=20).forEach(snippet=>{
+    out=out.split(snippet).join('');
+  });
+  return out.trim();
+}
+
 function renderMd(raw){
   let s=(raw||'').replace(/\r\n/g,'\n').replace(/\r/g,'\n');
   // ── Entity decode: must run FIRST so > lines become > for the blockquote
@@ -5401,6 +5411,9 @@ function renderMessages(options){
       content='**Error:** No response received after context compression. Please retry.';
     }
     const displayContent=isUser?_stripWorkspaceDisplayPrefix(content):content;
+    if(thinkingText&&!isUser){
+      thinkingText=_stripVisibleAssistantEchoFromThinking(thinkingText, displayContent);
+    }
     const isLastAssistant=!isUser&&vi===renderVisWithIdx.length-1;
     const nextRendered=renderVisWithIdx[vi+1];
     const isTurnFinalAssistant=!isUser&&(!nextRendered||!nextRendered.m||nextRendered.m.role!=='assistant');

tests/test_ui_tool_call_cleanup.py

@@ -11,6 +11,7 @@
 UI_JS = (REPO / "static" / "ui.js").read_text(encoding="utf-8")
 BOOT_JS = (REPO / "static" / "boot.js").read_text(encoding="utf-8")
 CSS = (REPO / "static" / "style.css").read_text(encoding="utf-8")
+MESSAGES_JS = (REPO / "static" / "messages.js").read_text(encoding="utf-8")
 
 
 def _function_body(src: str, name: str) -> str:
@@ -233,6 +234,32 @@ def test_live_activity_summary_shows_readable_progress_without_persisted_content
             "Readable progress must not reintroduce the noisy secondary tool-name list."
         )
 
+    def test_live_thinking_suppresses_visible_interim_echoes(self):
+        interim_match = re.search(r"source\.addEventListener\('interim_assistant',e=>\{(.*?)\n\s*\}\);", MESSAGES_JS, re.S)
+        assert interim_match, "interim_assistant listener not found"
+        interim_fn = interim_match.group(1)
+        live_thinking_fn = _function_body(MESSAGES_JS, "_liveThinkingText")
+
+        assert "visibleInterimSnippets.push(visible)" in interim_fn, (
+            "Visible interim commentary should be remembered so the live Thinking card does not echo it."
+        )
+        assert "_stripLiveVisibleAssistantEchoFromThinking" in live_thinking_fn, (
+            "Live Thinking text should suppress exact visible interim commentary echoes."
+        )
+
+    def test_settled_thinking_suppresses_visible_assistant_echoes(self):
+        render_fn = _function_body(UI_JS, "renderMessages")
+        helper = _function_body(UI_JS, "_stripVisibleAssistantEchoFromThinking")
+        assert "_stripVisibleAssistantEchoFromThinking(thinkingText, displayContent)" in render_fn, (
+            "Settled Thinking cards should not repeat text already rendered as visible assistant content."
+        )
+        assert "s.length>=20" in helper, (
+            "Thinking echo suppression should ignore tiny snippets to avoid over-stripping reasoning."
+        )
+        assert "out.split(snippet).join('')" in helper, (
+            "Thinking echo suppression should remove exact visible assistant snippets from reasoning display."
+        )
+
     def test_tools_and_thinking_share_one_collapsed_activity_dropdown(self):
         ui_min = re.sub(r"\s+", "", UI_JS)
         assert "functionensureActivityGroup(" in ui_min, (