diff --git a/server/index.js b/server/index.js
index ca451337..0995061b 100755
--- a/server/index.js
+++ b/server/index.js
@@ -36,7 +36,7 @@ import pty from 'node-pty';
 import fetch from 'node-fetch';
 import mime from 'mime-types';
 
-import { getProjects, getSessions, getSessionMessages, renameProject, deleteSession, deleteProject, addProjectManually, extractProjectDirectory, clearProjectDirectoryCache } from './projects.js';
+import { getProjects, getSessions, getSessionMessages, renameProject, deleteSession, updateSessionSummary, deleteProject, addProjectManually, extractProjectDirectory, clearProjectDirectoryCache } from './projects.js';
 import { spawnClaude, abortClaudeSession } from './claude-cli.js';
 import { spawnCursor, abortCursorSession } from './cursor-cli.js';
 import gitRoutes from './routes/git.js';
@@ -262,6 +262,18 @@ app.delete('/api/projects/:projectName/sessions/:sessionId', authenticateToken,
     }
 });
 
+// Update session summary endpoint
+app.put('/api/projects/:projectName/sessions/:sessionId/summary', authenticateToken, async (req, res) => {
+    try {
+        const { projectName, sessionId } = req.params;
+        const { summary } = req.body;
+        await updateSessionSummary(projectName, sessionId, summary);
+        res.json({ success: true });
+    } catch (error) {
+        res.status(500).json({ error: error.message });
+    }
+});
+
 // Delete project endpoint (only if empty)
 app.delete('/api/projects/:projectName', authenticateToken, async (req, res) => {
     try {
diff --git a/server/projects.js b/server/projects.js
index 1f228951..3c0df059 100755
--- a/server/projects.js
+++ b/server/projects.js
@@ -635,6 +635,76 @@ async function addProjectManually(projectPath, displayName = null) {
   };
 }
 
+async function updateSessionSummary(projectName, sessionId, newSummary) {
+  const projectDir = path.join(process.env.HOME, '.claude', 'projects', projectName);
+  
+  try {
+    const files = await fs.readdir(projectDir);
+    const jsonlFiles = files.filter(file => file.endsWith('.jsonl'));
+    
+    if (jsonlFiles.length === 0) {
+      throw new Error('No session files found for this project');
+    }
+    
+    // Find the file containing the session
+    for (const file of jsonlFiles) {
+      const jsonlFile = path.join(projectDir, file);
+      const content = await fs.readFile(jsonlFile, 'utf8');
+      const lines = content.split('\n').filter(line => line.trim());
+      
+      // Check if this file contains the session
+      const hasSession = lines.some(line => {
+        try {
+          const data = JSON.parse(line);
+          return data.sessionId === sessionId;
+        } catch (e) {
+          return false;
+        }
+      });
+      
+      if (hasSession) {
+        // Check if summary entry already exists
+        let summaryEntryExists = false;
+        const updatedLines = lines.map(line => {
+          try {
+            const data = JSON.parse(line);
+            if (data.sessionId === sessionId && data.type === 'summary') {
+              summaryEntryExists = true;
+              return JSON.stringify({
+                ...data,
+                summary: newSummary,
+                timestamp: new Date().toISOString()
+              });
+            }
+            return line;
+          } catch (e) {
+            return line;
+          }
+        });
+        
+        // If no summary entry exists, create one
+        if (!summaryEntryExists) {
+          const summaryEntry = {
+            sessionId: sessionId,
+            type: 'summary',
+            summary: newSummary,
+            timestamp: new Date().toISOString()
+          };
+          updatedLines.unshift(JSON.stringify(summaryEntry));
+        }
+        
+        // Write back to file
+        await fs.writeFile(jsonlFile, updatedLines.join('\n') + '\n', 'utf8');
+        return;
+      }
+    }
+    
+    throw new Error('Session not found');
+  } catch (error) {
+    throw new Error(`Failed to update session summary: ${error.message}`);
+  }
+}
+
 // Fetch Cursor sessions for a given project path
 async function getCursorSessions(projectPath) {
   try {
@@ -754,6 +824,7 @@ export {
   parseJsonlSessions,
   renameProject,
   deleteSession,
+  updateSessionSummary,
   isProjectEmpty,
   deleteProject,
   addProjectManually,
diff --git a/src/App.jsx b/src/App.jsx
index 1cbd7eb8..adb1a157 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -347,7 +347,37 @@ function AppContent() {
     );
   };
 
-
+  const handleUpdateSessionSummary = async (projectName, sessionId, newSummary) => {
+    try {
+      const response = await api.updateSessionSummary(projectName, sessionId, newSummary);
+      if (response.ok) {
+        // Update the session summary in local state
+        setProjects(prevProjects => 
+          prevProjects.map(project => 
+            project.name === projectName 
+              ? {
+                  ...project,
+                  sessions: project.sessions?.map(session => 
+                    session.id === sessionId 
+                      ? { ...session, summary: newSummary }
+                      : session
+                  ) || []
+                }
+              : project
+          )
+        );
+        
+        // Update selected session if it's the one being renamed
+        if (selectedSession?.id === sessionId) {
+          setSelectedSession(prev => ({ ...prev, summary: newSummary }));
+        }
+      } else {
+        console.error('Failed to update session summary');
+      }
+    } catch (error) {
+      console.error('Error updating session summary:', error);
+    }
+  };
 
   const handleSidebarRefresh = async () => {
     // Refresh only the sessions for all projects, don't change selected state
@@ -551,6 +581,7 @@ function AppContent() {
               onSessionSelect={handleSessionSelect}
               onNewSession={handleNewSession}
               onSessionDelete={handleSessionDelete}
+              onUpdateSessionSummary={handleUpdateSessionSummary}
               onProjectDelete={handleProjectDelete}
               isLoading={isLoadingProjects}
               onRefresh={handleSidebarRefresh}
@@ -596,6 +627,7 @@ function AppContent() {
               onSessionSelect={handleSessionSelect}
               onNewSession={handleNewSession}
               onSessionDelete={handleSessionDelete}
+              onUpdateSessionSummary={handleUpdateSessionSummary}
               onProjectDelete={handleProjectDelete}
               isLoading={isLoadingProjects}
               onRefresh={handleSidebarRefresh}
diff --git a/src/components/Sidebar.jsx b/src/components/Sidebar.jsx
index 36f3bbfe..242eba77 100644
--- a/src/components/Sidebar.jsx
+++ b/src/components/Sidebar.jsx
@@ -44,6 +44,7 @@ function Sidebar({
   onSessionSelect, 
   onNewSession,
   onSessionDelete,
+  onUpdateSessionSummary,
   onProjectDelete,
   isLoading,
   onRefresh,
@@ -1128,7 +1129,9 @@ function Sidebar({
                                       onKeyDown={(e) => {
                                         e.stopPropagation();
                                         if (e.key === 'Enter') {
-                                          updateSessionSummary(project.name, session.id, editingSessionName);
+                                          onUpdateSessionSummary(project.name, session.id, editingSessionName);
+                                          setEditingSession(null);
+                                          setEditingSessionName('');
                                         } else if (e.key === 'Escape') {
                                           setEditingSession(null);
                                           setEditingSessionName('');
@@ -1142,7 +1145,9 @@ function Sidebar({
                                       className="w-6 h-6 bg-green-50 hover:bg-green-100 dark:bg-green-900/20 dark:hover:bg-green-900/40 rounded flex items-center justify-center"
                                       onClick={(e) => {
                                         e.stopPropagation();
-                                        updateSessionSummary(project.name, session.id, editingSessionName);
+                                        onUpdateSessionSummary(project.name, session.id, editingSessionName);
+                                        setEditingSession(null);
+                                        setEditingSessionName('');
                                       }}
                                       title="Save"
                                     >
diff --git a/src/utils/api.js b/src/utils/api.js
index 22978512..b1be1027 100644
--- a/src/utils/api.js
+++ b/src/utils/api.js
@@ -62,6 +62,11 @@ export const api = {
     authenticatedFetch(`/api/projects/${projectName}/sessions/${sessionId}`, {
       method: 'DELETE',
     }),
+  updateSessionSummary: (projectName, sessionId, summary) =>
+    authenticatedFetch(`/api/projects/${projectName}/sessions/${sessionId}/summary`, {
+      method: 'PUT',
+      body: JSON.stringify({ summary }),
+    }),
   deleteProject: (projectName) =>
     authenticatedFetch(`/api/projects/${projectName}`, {
       method: 'DELETE',