diff --git a/server/claude-sdk.js b/server/claude-sdk.js
index 7239f81a4d..9149e25546 100644
--- a/server/claude-sdk.js
+++ b/server/claude-sdk.js
@@ -240,7 +240,7 @@ function addSession(sessionId, queryInstance, tempImagePaths = [], tempDir = nul
     status: 'active',
     tempImagePaths,
     tempDir,
-    writer
+    ws: writer && writer.isWebSocketWriter ? writer.ws : (writer && typeof writer.send === 'function' ? writer : null)
   });
 }
 
@@ -476,7 +476,7 @@ async function loadMcpConfig(cwd) {
  * @param {Object} ws - WebSocket connection
  * @returns {Promise<void>}
  */
-async function queryClaudeSDK(command, options = {}, ws) {
+async function queryClaudeSDK(command, options = {}, writer) {
   const { sessionId, sessionSummary } = options;
   let capturedSessionId = sessionId;
   let sessionCreatedSent = false;
@@ -485,8 +485,8 @@ async function queryClaudeSDK(command, options = {}, ws) {
 
   const emitNotification = (event) => {
     notifyUserIfEnabled({
-      userId: ws?.userId || null,
-      writer: ws,
+      userId: writer?.userId || null,
+      writer: writer,
       event
     });
   };
@@ -551,7 +551,7 @@ async function queryClaudeSDK(command, options = {}, ws) {
       }
 
       const requestId = createRequestId();
-      ws.send(createNormalizedMessage({ kind: 'permission_request', requestId, toolName, input, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
+      writer.send(createNormalizedMessage({ kind: 'permission_request', requestId, toolName, input, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
       emitNotification(createNotificationEvent({
         provider: 'claude',
         sessionId: capturedSessionId || sessionId || null,
@@ -573,7 +573,7 @@ async function queryClaudeSDK(command, options = {}, ws) {
           _receivedAt: new Date(),
         },
         onCancel: (reason) => {
-          ws.send(createNormalizedMessage({ kind: 'permission_cancelled', requestId, reason, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
+          writer.send(createNormalizedMessage({ kind: 'permission_cancelled', requestId, reason, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
         }
       });
       if (!decision) {
@@ -629,7 +629,7 @@ async function queryClaudeSDK(command, options = {}, ws) {
 
     // Track the query instance for abort capability
     if (capturedSessionId) {
-      addSession(capturedSessionId, queryInstance, tempImagePaths, tempDir, ws);
+      addSession(capturedSessionId, queryInstance, tempImagePaths, tempDir, writer);
     }
 
     // Process streaming messages
@@ -639,17 +639,17 @@ async function queryClaudeSDK(command, options = {}, ws) {
       if (message.session_id && !capturedSessionId) {
 
         capturedSessionId = message.session_id;
-        addSession(capturedSessionId, queryInstance, tempImagePaths, tempDir, ws);
+        addSession(capturedSessionId, queryInstance, tempImagePaths, tempDir, writer);
 
         // Set session ID on writer
-        if (ws.setSessionId && typeof ws.setSessionId === 'function') {
-          ws.setSessionId(capturedSessionId);
+        if (writer && typeof writer.setSessionId === 'function') {
+          writer.setSessionId(capturedSessionId);
         }
 
         // Send session-created event only once for new sessions
         if (!sessionId && !sessionCreatedSent) {
           sessionCreatedSent = true;
-          ws.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, sessionId: capturedSessionId, provider: 'claude' }));
+          writer.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, sessionId: capturedSessionId, provider: 'claude' }));
         }
       } else {
         // session_id already captured
@@ -666,7 +666,7 @@ async function queryClaudeSDK(command, options = {}, ws) {
         if (transformedMessage.parentToolUseId && !msg.parentToolUseId) {
           msg.parentToolUseId = transformedMessage.parentToolUseId;
         }
-        ws.send(msg);
+        writer.send(msg);
       }
 
       // Extract and send token budget updates from result messages
@@ -677,7 +677,7 @@ async function queryClaudeSDK(command, options = {}, ws) {
         }
         const tokenBudgetData = extractTokenBudget(message);
         if (tokenBudgetData) {
-          ws.send(createNormalizedMessage({ kind: 'status', text: 'token_budget', tokenBudget: tokenBudgetData, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
+          writer.send(createNormalizedMessage({ kind: 'status', text: 'token_budget', tokenBudget: tokenBudgetData, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
         }
       }
     }
@@ -691,9 +691,9 @@ async function queryClaudeSDK(command, options = {}, ws) {
     await cleanupTempFiles(tempImagePaths, tempDir);
 
     // Send completion event
-    ws.send(createNormalizedMessage({ kind: 'complete', exitCode: 0, isNewSession: !sessionId && !!command, sessionId: capturedSessionId, provider: 'claude' }));
+    writer.send(createNormalizedMessage({ kind: 'complete', exitCode: 0, isNewSession: !sessionId && !!command, sessionId: capturedSessionId, provider: 'claude' }));
     notifyRunStopped({
-      userId: ws?.userId || null,
+      userId: writer?.userId || null,
       provider: 'claude',
       sessionId: capturedSessionId || sessionId || null,
       sessionName: sessionSummary,
@@ -719,9 +719,9 @@ async function queryClaudeSDK(command, options = {}, ws) {
       : error.message;
 
     // Send error to WebSocket
-    ws.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
+    writer.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: capturedSessionId || sessionId || null, provider: 'claude' }));
     notifyRunFailed({
-      userId: ws?.userId || null,
+      userId: writer?.userId || null,
       provider: 'claude',
       sessionId: capturedSessionId || sessionId || null,
       sessionName: sessionSummary,
@@ -765,6 +765,23 @@ async function abortClaudeSDKSession(sessionId) {
   }
 }
 
+/**
+ * Aborts all sessions associated with a specific WebSocket
+ * @param {WebSocket} ws - The WebSocket to match
+ * @returns {number} - Number of sessions aborted
+ */
+function abortClaudeSDKSessionsForWebSocket(ws) {
+  let count = 0;
+  for (const [id, session] of activeSessions.entries()) {
+    if (session.ws === ws && session.status === 'active') {
+      console.log(`[Claude] Aborting orphaned session ${id} due to WebSocket disconnect`);
+      abortClaudeSDKSession(id);
+      count++;
+    }
+  }
+  return count;
+}
+
 /**
  * Checks if an SDK session is currently active
  * @param {string} sessionId - Session identifier
@@ -780,7 +797,13 @@ function isClaudeSDKSessionActive(sessionId) {
  * @returns {Array<string>} Array of active session IDs
  */
 function getActiveClaudeSDKSessions() {
-  return getAllSessions();
+  const activeIds = [];
+  for (const [id, session] of activeSessions.entries()) {
+    if (session.status === 'active') {
+      activeIds.push(id);
+    }
+  }
+  return activeIds;
 }
 
 /**
@@ -820,10 +843,11 @@ function reconnectSessionWriter(sessionId, newRawWs) {
   return true;
 }
 
-// Export public API
+// Export public API - Fixed duplicate export issue
 export {
   queryClaudeSDK,
   abortClaudeSDKSession,
+  abortClaudeSDKSessionsForWebSocket,
   isClaudeSDKSessionActive,
   getActiveClaudeSDKSessions,
   resolveToolApproval,
diff --git a/server/cursor-cli.js b/server/cursor-cli.js
index 66af16ef50..2a0b495e9a 100644
--- a/server/cursor-cli.js
+++ b/server/cursor-cli.js
@@ -1,5 +1,6 @@
 import { spawn } from 'child_process';
 import crossSpawn from 'cross-spawn';
+import { StringDecoder } from 'string_decoder';
 import { notifyRunFailed, notifyRunStopped } from './services/notification-orchestrator.js';
 import { sessionsService } from './modules/providers/services/sessions.service.js';
 import { providerAuthService } from './modules/providers/services/provider-auth.service.js';
@@ -25,7 +26,7 @@ function isWorkspaceTrustPrompt(text = '') {
   return WORKSPACE_TRUST_PATTERNS.some((pattern) => pattern.test(text));
 }
 
-async function spawnCursor(command, options = {}, ws) {
+async function spawnCursor(command, options = {}, writer) {
   return new Promise(async (resolve, reject) => {
     const { sessionId, projectPath, cwd, resume, toolsSettings, skipPermissions, model, sessionSummary } = options;
     let capturedSessionId = sessionId; // Track session ID throughout the process
@@ -97,7 +98,7 @@ async function spawnCursor(command, options = {}, ws) {
         const finalSessionId = capturedSessionId || sessionId || processKey;
         if (code === 0 && !error) {
           notifyRunStopped({
-            userId: ws?.userId || null,
+            userId: writer?.userId || null,
             provider: 'cursor',
             sessionId: finalSessionId,
             sessionName: sessionSummary,
@@ -107,7 +108,7 @@ async function spawnCursor(command, options = {}, ws) {
         }
 
         notifyRunFailed({
-          userId: ws?.userId || null,
+          userId: writer?.userId || null,
           provider: 'cursor',
           sessionId: finalSessionId,
           sessionName: sessionSummary,
@@ -129,6 +130,11 @@ async function spawnCursor(command, options = {}, ws) {
         env: { ...process.env } // Inherit all environment variables
       });
 
+      // Store WebSocket reference for cleanup on disconnect
+      if (writer && writer.ws) {
+        cursorProcess.ws = writer.ws;
+      }
+
       activeCursorProcesses.set(processKey, cursorProcess);
 
       const shouldSuppressForTrustRetry = (text) => {
@@ -168,14 +174,12 @@ async function spawnCursor(command, options = {}, ws) {
                   }
 
                   // Set session ID on writer (for API endpoint compatibility)
-                  if (ws.setSessionId && typeof ws.setSessionId === 'function') {
-                    ws.setSessionId(capturedSessionId);
-                  }
+                  writer && typeof writer.setSessionId === 'function' && writer.setSessionId(capturedSessionId);
 
                   // Send session-created event only once for new sessions
                   if (!sessionId && !sessionCreatedSent) {
                     sessionCreatedSent = true;
-                    ws.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, model: response.model, cwd: response.cwd, sessionId: capturedSessionId, provider: 'cursor' }));
+                    writer.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, model: response.model, cwd: response.cwd, sessionId: capturedSessionId, provider: 'cursor' }));
                   }
                 }
 
@@ -191,7 +195,7 @@ async function spawnCursor(command, options = {}, ws) {
               // Accumulate assistant message chunks
               if (response.message && response.message.content && response.message.content.length > 0) {
                 const normalized = sessionsService.normalizeMessage('cursor', response, capturedSessionId || sessionId || null);
-                for (const msg of normalized) ws.send(msg);
+                for (const msg of normalized) writer.send(msg);
               }
               break;
 
@@ -199,7 +203,7 @@ async function spawnCursor(command, options = {}, ws) {
               // Session complete — send stream end + lifecycle complete with result payload
               console.log('Cursor session result:', response);
               const resultText = typeof response.result === 'string' ? response.result : '';
-              ws.send(createNormalizedMessage({
+              writer.send(createNormalizedMessage({
                 kind: 'complete',
                 exitCode: response.subtype === 'success' ? 0 : 1,
                 resultText,
@@ -221,13 +225,16 @@ async function spawnCursor(command, options = {}, ws) {
 
           // If not JSON, send as stream delta via adapter
           const normalized = sessionsService.normalizeMessage('cursor', line, capturedSessionId || sessionId || null);
-          for (const msg of normalized) ws.send(msg);
+          for (const msg of normalized) writer.send(msg);
         }
       };
 
+      const stdoutDecoder = new StringDecoder('utf8');
+      const stderrDecoder = new StringDecoder('utf8');
+
       // Handle stdout (streaming JSON responses)
       cursorProcess.stdout.on('data', (data) => {
-        const rawOutput = data.toString();
+        const rawOutput = stdoutDecoder.write(data);
         console.log('Cursor CLI stdout:', rawOutput);
 
         // Stream chunks can split JSON objects across packets; keep trailing partial line.
@@ -242,14 +249,14 @@ async function spawnCursor(command, options = {}, ws) {
 
       // Handle stderr
       cursorProcess.stderr.on('data', (data) => {
-        const stderrText = data.toString();
+        const stderrText = stderrDecoder.write(data);
         console.error('Cursor CLI stderr:', stderrText);
 
         if (shouldSuppressForTrustRetry(stderrText)) {
           return;
         }
 
-        ws.send(createNormalizedMessage({ kind: 'error', content: stderrText, sessionId: capturedSessionId || sessionId || null, provider: 'cursor' }));
+        writer.send(createNormalizedMessage({ kind: 'error', content: stderrText, sessionId: capturedSessionId || sessionId || null, provider: 'cursor' }));
       });
 
       // Handle process completion
@@ -276,7 +283,7 @@ async function spawnCursor(command, options = {}, ws) {
           return;
         }
 
-        ws.send(createNormalizedMessage({ kind: 'complete', exitCode: code, isNewSession: !sessionId && !!command, sessionId: finalSessionId, provider: 'cursor' }));
+        writer.send(createNormalizedMessage({ kind: 'complete', exitCode: code, isNewSession: !sessionId && !!command, sessionId: finalSessionId, provider: 'cursor' }));
 
         if (code === 0) {
           notifyTerminalState({ code });
@@ -301,7 +308,7 @@ async function spawnCursor(command, options = {}, ws) {
           ? 'Cursor CLI is not installed. Please install it from https://cursor.com'
           : error.message;
 
-        ws.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: capturedSessionId || sessionId || null, provider: 'cursor' }));
+        writer.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: capturedSessionId || sessionId || null, provider: 'cursor' }));
         notifyTerminalState({ error });
 
         settleOnce(() => reject(error));
@@ -326,6 +333,18 @@ function abortCursorSession(sessionId) {
   return false;
 }
 
+function abortCursorSessionsForWebSocket(ws) {
+  let count = 0;
+  for (const [sessionId, proc] of activeCursorProcesses.entries()) {
+    if (proc.ws === ws) {
+      console.log(`[Cursor] Aborting orphaned session ${sessionId} due to WebSocket disconnect`);
+      abortCursorSession(sessionId);
+      count++;
+    }
+  }
+  return count;
+}
+
 function isCursorSessionActive(sessionId) {
   return activeCursorProcesses.has(sessionId);
 }
@@ -337,6 +356,7 @@ function getActiveCursorSessions() {
 export {
   spawnCursor,
   abortCursorSession,
+  abortCursorSessionsForWebSocket,
   isCursorSessionActive,
   getActiveCursorSessions
 };
diff --git a/server/gemini-cli.js b/server/gemini-cli.js
index 2e68a9388f..229d639228 100644
--- a/server/gemini-cli.js
+++ b/server/gemini-cli.js
@@ -1,5 +1,6 @@
 import { spawn } from 'child_process';
 import crossSpawn from 'cross-spawn';
+import { StringDecoder } from 'string_decoder';
 
 // Use cross-spawn on Windows for correct .cmd resolution (same pattern as cursor-cli.js)
 const spawnFunction = process.platform === 'win32' ? crossSpawn : spawn;
@@ -14,7 +15,7 @@ import { createNormalizedMessage } from './shared/utils.js';
 
 let activeGeminiProcesses = new Map(); // Track active processes by session ID
 
-async function spawnGemini(command, options = {}, ws) {
+async function spawnGemini(command, options = {}, writer) {
     const { sessionId, projectPath, cwd, toolsSettings, permissionMode, images, sessionSummary } = options;
     let capturedSessionId = sessionId; // Track session ID throughout the process
     let sessionCreatedSent = false; // Track if we've already sent session-created event
@@ -187,7 +188,7 @@ async function spawnGemini(command, options = {}, ws) {
             const finalSessionId = capturedSessionId || sessionId || processKey;
             if (code === 0 && !error) {
                 notifyRunStopped({
-                    userId: ws?.userId || null,
+                    userId: writer?.userId || null,
                     provider: 'gemini',
                     sessionId: finalSessionId,
                     sessionName: sessionSummary,
@@ -197,7 +198,7 @@ async function spawnGemini(command, options = {}, ws) {
             }
 
             notifyRunFailed({
-                userId: ws?.userId || null,
+                userId: writer?.userId || null,
                 provider: 'gemini',
                 sessionId: finalSessionId,
                 sessionName: sessionSummary,
@@ -209,6 +210,11 @@ async function spawnGemini(command, options = {}, ws) {
         geminiProcess.tempImagePaths = tempImagePaths;
         geminiProcess.tempDir = tempDir;
 
+        // Store WebSocket reference for cleanup on disconnect
+        if (writer && writer.ws) {
+            geminiProcess.ws = writer.ws;
+        }
+
         // Store process reference for potential abort
         const processKey = capturedSessionId || sessionId || Date.now().toString();
         activeGeminiProcesses.set(processKey, geminiProcess);
@@ -226,9 +232,9 @@ async function spawnGemini(command, options = {}, ws) {
         const startTimeout = () => {
             if (timeout) clearTimeout(timeout);
             timeout = setTimeout(() => {
-                const socketSessionId = typeof ws.getSessionId === 'function' ? ws.getSessionId() : (capturedSessionId || sessionId || processKey);
+                const socketSessionId = writer && typeof writer.getSessionId === 'function' ? writer.getSessionId() : (capturedSessionId || sessionId || processKey);
                 terminalFailureReason = `Gemini CLI timeout - no response received for ${timeoutMs / 1000} seconds`;
-                ws.send(createNormalizedMessage({ kind: 'error', content: terminalFailureReason, sessionId: socketSessionId, provider: 'gemini' }));
+                writer.send(createNormalizedMessage({ kind: 'error', content: terminalFailureReason, sessionId: socketSessionId, provider: 'gemini' }));
                 try {
                     geminiProcess.kill('SIGTERM');
                 } catch (e) { }
@@ -244,8 +250,8 @@ async function spawnGemini(command, options = {}, ws) {
 
         // Create response handler for NDJSON buffering
         let responseHandler;
-        if (ws) {
-            responseHandler = new GeminiResponseHandler(ws, {
+        if (writer) {
+            responseHandler = new GeminiResponseHandler(writer, {
                 onContentFragment: (content) => {
                     if (assistantBlocks.length > 0 && assistantBlocks[assistantBlocks.length - 1].type === 'text') {
                         assistantBlocks[assistantBlocks.length - 1].text += content;
@@ -287,9 +293,12 @@ async function spawnGemini(command, options = {}, ws) {
             });
         }
 
+        const stdoutDecoder = new StringDecoder('utf8');
+        const stderrDecoder = new StringDecoder('utf8');
+
         // Handle stdout
         geminiProcess.stdout.on('data', (data) => {
-            const rawOutput = data.toString();
+            const rawOutput = stdoutDecoder.write(data);
             startTimeout(); // Re-arm the timeout
 
             // For new sessions, create a session ID FIRST
@@ -311,10 +320,10 @@ async function spawnGemini(command, options = {}, ws) {
                     activeGeminiProcesses.set(capturedSessionId, geminiProcess);
                 }
 
-                ws.setSessionId && typeof ws.setSessionId === 'function' && ws.setSessionId(capturedSessionId);
+                writer && typeof writer.setSessionId === 'function' && writer.setSessionId(capturedSessionId);
 
-                ws.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, sessionId: capturedSessionId, provider: 'gemini' }));
-            }
+                writer.send(createNormalizedMessage({ kind: 'session_created', newSessionId: capturedSessionId, sessionId: capturedSessionId, provider: 'gemini' }));
+                }
 
             if (responseHandler) {
                 responseHandler.processData(rawOutput);
@@ -325,14 +334,14 @@ async function spawnGemini(command, options = {}, ws) {
                 } else {
                     assistantBlocks.push({ type: 'text', text: rawOutput });
                 }
-                const socketSessionId = typeof ws.getSessionId === 'function' ? ws.getSessionId() : (capturedSessionId || sessionId);
-                ws.send(createNormalizedMessage({ kind: 'stream_delta', content: rawOutput, sessionId: socketSessionId, provider: 'gemini' }));
+                const socketSessionId = writer && typeof writer.getSessionId === 'function' ? writer.getSessionId() : (capturedSessionId || sessionId);
+                writer.send(createNormalizedMessage({ kind: 'stream_delta', content: rawOutput, sessionId: socketSessionId, provider: 'gemini' }));
             }
         });
 
         // Handle stderr
         geminiProcess.stderr.on('data', (data) => {
-            const errorMsg = data.toString();
+            const errorMsg = stderrDecoder.write(data);
 
             // Filter out deprecation warnings and "Loaded cached credentials" message
             if (errorMsg.includes('[DEP0040]') ||
@@ -342,8 +351,8 @@ async function spawnGemini(command, options = {}, ws) {
                 return;
             }
 
-            const socketSessionId = typeof ws.getSessionId === 'function' ? ws.getSessionId() : (capturedSessionId || sessionId);
-            ws.send(createNormalizedMessage({ kind: 'error', content: errorMsg, sessionId: socketSessionId, provider: 'gemini' }));
+            const socketSessionId = writer && typeof writer.getSessionId === 'function' ? writer.getSessionId() : (capturedSessionId || sessionId);
+            writer.send(createNormalizedMessage({ kind: 'error', content: errorMsg, sessionId: socketSessionId, provider: 'gemini' }));
         });
 
         // Handle process completion
@@ -365,7 +374,7 @@ async function spawnGemini(command, options = {}, ws) {
                 sessionManager.addMessage(finalSessionId, 'assistant', assistantBlocks);
             }
 
-            ws.send(createNormalizedMessage({ kind: 'complete', exitCode: code, isNewSession: !sessionId && !!command, sessionId: finalSessionId, provider: 'gemini' }));
+            writer.send(createNormalizedMessage({ kind: 'complete', exitCode: code, isNewSession: !sessionId && !!command, sessionId: finalSessionId, provider: 'gemini' }));
 
             // Clean up temporary image files if any
             if (geminiProcess.tempImagePaths && geminiProcess.tempImagePaths.length > 0) {
@@ -385,8 +394,8 @@ async function spawnGemini(command, options = {}, ws) {
                 if (code === 127) {
                     const installed = await providerAuthService.isProviderInstalled('gemini');
                     if (!installed) {
-                        const socketSessionId = typeof ws.getSessionId === 'function' ? ws.getSessionId() : finalSessionId;
-                        ws.send(createNormalizedMessage({ kind: 'error', content: 'Gemini CLI is not installed. Please install it first: https://github.com/google-gemini/gemini-cli', sessionId: socketSessionId, provider: 'gemini' }));
+                        const socketSessionId = writer && typeof writer.getSessionId === 'function' ? writer.getSessionId() : finalSessionId;
+                        writer.send(createNormalizedMessage({ kind: 'error', content: 'Gemini CLI is not installed. Please install it first: https://github.com/google-gemini/gemini-cli', sessionId: socketSessionId, provider: 'gemini' }));
                     }
                 }
 
@@ -410,8 +419,8 @@ async function spawnGemini(command, options = {}, ws) {
                 ? 'Gemini CLI is not installed. Please install it first: https://github.com/google-gemini/gemini-cli'
                 : error.message;
 
-            const errorSessionId = typeof ws.getSessionId === 'function' ? ws.getSessionId() : finalSessionId;
-            ws.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: errorSessionId, provider: 'gemini' }));
+            const errorSessionId = writer && typeof writer.getSessionId === 'function' ? writer.getSessionId() : finalSessionId;
+            writer.send(createNormalizedMessage({ kind: 'error', content: errorContent, sessionId: errorSessionId, provider: 'gemini' }));
             notifyTerminalState({ error });
 
             reject(error);
@@ -453,6 +462,18 @@ function abortGeminiSession(sessionId) {
     return false;
 }
 
+function abortGeminiSessionsForWebSocket(ws) {
+    let count = 0;
+    for (const [sessionId, proc] of activeGeminiProcesses.entries()) {
+        if (proc.ws === ws) {
+            console.log(`[Gemini] Aborting orphaned session ${sessionId} due to WebSocket disconnect`);
+            abortGeminiSession(sessionId);
+            count++;
+        }
+    }
+    return count;
+}
+
 function isGeminiSessionActive(sessionId) {
     return activeGeminiProcesses.has(sessionId);
 }
@@ -464,6 +485,7 @@ function getActiveGeminiSessions() {
 export {
     spawnGemini,
     abortGeminiSession,
+    abortGeminiSessionsForWebSocket,
     isGeminiSessionActive,
     getActiveGeminiSessions
 };
diff --git a/server/gemini-response-handler.js b/server/gemini-response-handler.js
index b0a1748550..843eb5e0b0 100644
--- a/server/gemini-response-handler.js
+++ b/server/gemini-response-handler.js
@@ -34,7 +34,7 @@ class GeminiResponseHandler {
   }
 
   handleEvent(event) {
-    const sid = typeof this.ws.getSessionId === 'function' ? this.ws.getSessionId() : null;
+    const sid = this.ws && typeof this.ws.getSessionId === 'function' ? this.ws.getSessionId() : null;
 
     if (event.type === 'init') {
       if (this.onInit) {
@@ -58,7 +58,9 @@ class GeminiResponseHandler {
     // Normalize via adapter and send all resulting messages
     const normalized = sessionsService.normalizeMessage('gemini', event, sid);
     for (const msg of normalized) {
-      this.ws.send(msg);
+      if (this.ws) {
+        this.ws.send(msg);
+      }
     }
   }
 
diff --git a/server/index.js b/server/index.js
index 62d85130ba..35fc8c0243 100755
--- a/server/index.js
+++ b/server/index.js
@@ -248,6 +248,22 @@ const wss = new WebSocketServer({
     }
 });
 
+// Setup heartbeat interval to detect dead connections
+const heartbeatInterval = setInterval(() => {
+    wss.clients.forEach((ws) => {
+        if (ws.isAlive === false) {
+            console.log('🔌 Terminating dead WebSocket connection');
+            return ws.terminate();
+        }
+        ws.isAlive = false;
+        ws.ping();
+    });
+}, 30000); // 30 seconds
+
+wss.on('close', () => {
+    clearInterval(heartbeatInterval);
+});
+
 // Make WebSocket server available to routes
 app.locals.wss = wss;
 
@@ -1339,6 +1355,10 @@ wss.on('connection', (ws, request) => {
     const url = request.url;
     console.log('[INFO] Client connected to:', url);
 
+    // Initial liveness state for heartbeat
+    ws.isAlive = true;
+    ws.on('pong', () => { ws.isAlive = true; });
+
     // Parse URL to get pathname without query parameters
     const urlObj = new URL(url, 'http://localhost');
     const pathname = urlObj.pathname;
@@ -1371,9 +1391,15 @@ class WebSocketWriter {
     }
 
     send(data) {
-        if (this.ws.readyState === 1) { // WebSocket.OPEN
-            this.ws.send(JSON.stringify(data));
+        try {
+            if (this.ws && this.ws.readyState === 1) { // WebSocket.OPEN
+                this.ws.send(JSON.stringify(data));
+                return true;
+            }
+        } catch (error) {
+            console.error('[WebSocketWriter] Error sending message:', error.message);
         }
+        return false;
     }
 
     updateWebSocket(newRawWs) {
@@ -1534,6 +1560,22 @@ function handleChatConnection(ws, request) {
         console.log('🔌 Chat client disconnected');
         // Remove from connected clients
         connectedClients.delete(ws);
+
+        // Abort any active sessions associated with this specific WebSocket
+        try {
+            const counts = {
+                claude: abortClaudeSDKSessionsForWebSocket(ws),
+                cursor: abortCursorSessionsForWebSocket(ws),
+                codex: abortCodexSessionsForWebSocket(ws),
+                gemini: abortGeminiSessionsForWebSocket(ws)
+            };
+            const total = counts.claude + counts.cursor + counts.codex + counts.gemini;
+            if (total > 0) {
+                console.log(`🧹 Cleaned up ${total} orphaned sessions (Claude:${counts.claude}, Cursor:${counts.cursor}, Codex:${counts.codex}, Gemini:${counts.gemini})`);
+            }
+        } catch (err) {
+            console.error('[Cleanup] Error during session cleanup:', err.message);
+        }
     });
 }
 
@@ -2312,6 +2354,9 @@ async function startServer() {
         // Initialize authentication database
         await initializeDatabase();
 
+        // Ensure Gemini session store is loaded from disk before accepting requests
+        await sessionManager.ready;
+
         // Configure Web Push (VAPID keys)
         configureWebPush();
 
diff --git a/server/openai-codex.js b/server/openai-codex.js
index 5a7a9007ea..ad841e3023 100644
--- a/server/openai-codex.js
+++ b/server/openai-codex.js
@@ -192,7 +192,7 @@ function mapPermissionModeToCodexOptions(permissionMode) {
  * @param {object} options - Options including cwd, sessionId, model, permissionMode
  * @param {WebSocket|object} ws - WebSocket connection or response writer
  */
-export async function queryCodex(command, options = {}, ws) {
+async function queryCodex(command, options = {}, ws) {
   const {
     sessionId,
     sessionSummary,
@@ -240,7 +240,8 @@ export async function queryCodex(command, options = {}, ws) {
       codex,
       status: 'running',
       abortController,
-      startedAt: new Date().toISOString()
+      startedAt: new Date().toISOString(),
+      ws: ws && ws.isWebSocketWriter ? ws.ws : ws
     });
 
     // Send session created event
@@ -344,7 +345,7 @@ export async function queryCodex(command, options = {}, ws) {
  * @param {string} sessionId - Session ID to abort
  * @returns {boolean} - Whether abort was successful
  */
-export function abortCodexSession(sessionId) {
+function abortCodexSession(sessionId) {
   const session = activeCodexSessions.get(sessionId);
 
   if (!session) {
@@ -361,12 +362,29 @@ export function abortCodexSession(sessionId) {
   return true;
 }
 
+/**
+ * Abort all Codex sessions associated with a specific WebSocket
+ * @param {WebSocket} ws - The WebSocket to match
+ * @returns {number} - Number of sessions aborted
+ */
+export function abortCodexSessionsForWebSocket(ws) {
+  let count = 0;
+  for (const [id, session] of activeCodexSessions.entries()) {
+    if (session.ws === ws && session.status === 'running') {
+      console.log(`[Codex] Aborting orphaned session ${id} due to WebSocket disconnect`);
+      abortCodexSession(id);
+      count++;
+    }
+  }
+  return count;
+}
+
 /**
  * Check if a session is active
  * @param {string} sessionId - Session ID to check
  * @returns {boolean} - Whether session is active
  */
-export function isCodexSessionActive(sessionId) {
+function isCodexSessionActive(sessionId) {
   const session = activeCodexSessions.get(sessionId);
   return session?.status === 'running';
 }
@@ -375,7 +393,7 @@ export function isCodexSessionActive(sessionId) {
  * Get all active sessions
  * @returns {Array} - Array of active session info
  */
-export function getActiveCodexSessions() {
+function getActiveCodexSessions() {
   const sessions = [];
 
   for (const [id, session] of activeCodexSessions.entries()) {
@@ -391,6 +409,13 @@ export function getActiveCodexSessions() {
   return sessions;
 }
 
+export {
+  queryCodex,
+  abortCodexSession,
+  isCodexSessionActive,
+  getActiveCodexSessions
+};
+
 /**
  * Helper to send message via WebSocket or writer
  * @param {WebSocket|object} ws - WebSocket or response writer
@@ -398,12 +423,14 @@ export function getActiveCodexSessions() {
  */
 function sendMessage(ws, data) {
   try {
-    if (ws.isSSEStreamWriter || ws.isWebSocketWriter) {
+    if (ws && (ws.isSSEStreamWriter || ws.isWebSocketWriter)) {
       // Writer handles stringification (SSEStreamWriter or WebSocketWriter)
       ws.send(data);
-    } else if (typeof ws.send === 'function') {
+    } else if (ws && typeof ws.send === 'function') {
       // Raw WebSocket - stringify here
-      ws.send(JSON.stringify(data));
+      if (ws.readyState === 1) { // WebSocket.OPEN
+        ws.send(JSON.stringify(data));
+      }
     }
   } catch (error) {
     console.error('[Codex] Error sending message:', error);
diff --git a/src/components/sidebar/view/subcomponents/SidebarHeader.tsx b/src/components/sidebar/view/subcomponents/SidebarHeader.tsx
index 551c00956b..b6f34e6917 100644
--- a/src/components/sidebar/view/subcomponents/SidebarHeader.tsx
+++ b/src/components/sidebar/view/subcomponents/SidebarHeader.tsx
@@ -1,9 +1,10 @@
-import { Folder, FolderPlus, MessageSquare, Plus, RefreshCw, Search, X, PanelLeftClose } from 'lucide-react';
+import { Folder, FolderPlus, MessageSquare, Plus, RefreshCw, Search, X, PanelLeftClose, Globe } from 'lucide-react';
 import type { TFunction } from 'i18next';
 import { Button, Input } from '../../../../shared/view/ui';
 import { IS_PLATFORM } from '../../../../constants/config';
 import { cn } from '../../../../lib/utils';
 import GitHubStarBadge from './GitHubStarBadge';
+import { useWebSocket } from '../../../../contexts/WebSocketContext';
 
 type SearchMode = 'projects' | 'conversations';
 
@@ -40,12 +41,21 @@ export default function SidebarHeader({
   onCollapseSidebar,
   t,
 }: SidebarHeaderProps) {
+  const { isConnected } = useWebSocket();
+
   const LogoBlock = () => (
     <div className="flex min-w-0 items-center gap-2.5">
-      <div className="flex h-7 w-7 flex-shrink-0 items-center justify-center rounded-lg bg-primary/90 shadow-sm">
+      <div className="relative flex h-7 w-7 flex-shrink-0 items-center justify-center rounded-lg bg-primary/90 shadow-sm">
         <svg className="h-3.5 w-3.5 text-primary-foreground" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth={2.2} strokeLinecap="round" strokeLinejoin="round">
           <path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z" />
         </svg>
+        <div 
+          className={cn(
+            "absolute -right-0.5 -top-0.5 h-2 w-2 rounded-full border border-background shadow-sm",
+            isConnected ? "bg-emerald-500" : "bg-red-500 animate-pulse"
+          )}
+          title={isConnected ? t('websocket.connected', { defaultValue: 'Connected' }) : t('websocket.disconnected', { defaultValue: 'Disconnected' })}
+        />
       </div>
       <h1 className="truncate text-sm font-semibold tracking-tight text-foreground">{t('app.title')}</h1>
     </div>