Real-time comment sync, MCP server expansion, multi-tab terminal, UI fixes

- Fix Socket.IO v0.9 ack parser to handle acks without data (6:::N format),
  fixing comment creation stuck at "sending"
- Rewrite comment sync to use local state updates from socket events
  (new-comment, resolve-thread, reopen-thread, delete-thread, edit-message,
  delete-message) instead of REST re-fetches — instant UI updates
- Optimistic updates for all comment actions (resolve, reopen, delete, reply, edit)
- Fetch threads + contexts on project connect so editor highlights are correct
  from startup, not only when review panel is opened
- Add comment context to store immediately after creation for instant highlight
- Rename MCP server from overleaf-comments to lattex, add 6 new tools:
  reopen_comment, delete_comment, get_chat_messages, send_chat_message,
  list_project_files, compile_latex — all auto-granted permissions
- Refactor terminal from fixed Terminal/Claude tabs to dynamic multi-tab with
  bottom tab bar and unlimited new terminal creation
- Fix chat panel layout overflow pushing other components

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

11 files changed, 1132 insertions, 196 deletions

diff --git a/src/main/index.ts b/src/main/index.ts
index 96a225c..6e0b40b 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -3,7 +3,7 @@
 
 import { app, BrowserWindow, ipcMain, dialog, shell, net } from 'electron'
 import { join, basename } from 'path'
-import { readFile, writeFile } from 'fs/promises'
+import { readFile, writeFile, mkdir as mkdirAsync, unlink } from 'fs/promises'
 import { spawn } from 'child_process'
 import * as pty from 'node-pty'
 import { OverleafSocket, type RootFolder, type SubFolder, type JoinDocResult } from './overleafSocket'
@@ -15,6 +15,24 @@ const ptyInstances = new Map<string, pty.IPty>()
 let overleafSock: OverleafSocket | null = null
 let compilationManager: CompilationManager | null = null
 let fileSyncBridge: FileSyncBridge | null = null
+let mcpStateDir = ''           // syncDir for .lattex-mcp.json
+let mcpProjectId = ''
+let mcpCommentContexts: Record<string, { file: string; text: string; pos: number }> = {}
+let mcpPathDocMap: Record<string, string> = {}  // relPath → docId for MCP
+
+async function writeMcpState(): Promise<void> {
+  if (!mcpStateDir || !mcpProjectId) return
+  try {
+    const state = {
+      projectId: mcpProjectId,
+      cookie: overleafSessionCookie,
+      csrf: overleafCsrfToken,
+      commentContexts: mcpCommentContexts,
+      pathDocMap: mcpPathDocMap
+    }
+    await writeFile(join(mcpStateDir, '.lattex-mcp.json'), JSON.stringify(state, null, 2))
+  } catch { /* ignore */ }
+}
 
 function createWindow(): void {
   mainWindow = new BrowserWindow({
@@ -45,6 +63,7 @@ function sendToRenderer(channel: string, ...args: unknown[]) {
   }
 }
 
+
 ipcMain.handle('fs:readFile', async (_e, filePath: string) => {
   return readFile(filePath, 'utf-8')
 })
@@ -359,22 +378,27 @@ ipcMain.handle('overleaf:replyThread', async (_e, projectId: string, threadId: s
 })
 
 // Resolve a thread
-ipcMain.handle('overleaf:resolveThread', async (_e, projectId: string, threadId: string) => {
+ipcMain.handle('overleaf:resolveThread', async (_e, projectId: string, threadId: string, docId?: string) => {
   if (!overleafSessionCookie) return { success: false }
-  const result = await overleafFetch(`/project/${projectId}/thread/${threadId}/resolve`, {
+  // docId is required in the URL path for resolve
+  const docSegment = docId ? `/doc/${docId}` : ''
+  const result = await overleafFetch(`/project/${projectId}${docSegment}/thread/${threadId}/resolve`, {
     method: 'POST',
     body: '{}'
   })
+  if (!result.ok) console.log(`[resolveThread] failed: ${result.status}`, result.data)
   return { success: result.ok }
 })
 
 // Reopen a thread
-ipcMain.handle('overleaf:reopenThread', async (_e, projectId: string, threadId: string) => {
+ipcMain.handle('overleaf:reopenThread', async (_e, projectId: string, threadId: string, docId?: string) => {
   if (!overleafSessionCookie) return { success: false }
-  const result = await overleafFetch(`/project/${projectId}/thread/${threadId}/reopen`, {
+  const docSegment = docId ? `/doc/${docId}` : ''
+  const result = await overleafFetch(`/project/${projectId}${docSegment}/thread/${threadId}/reopen`, {
     method: 'POST',
     body: '{}'
   })
+  if (!result.ok) console.log(`[reopenThread] failed: ${result.status}`, result.data)
   return { success: result.ok }
 })
 
@@ -406,7 +430,7 @@ ipcMain.handle('overleaf:deleteThread', async (_e, projectId: string, docId: str
   return { success: result.ok }
 })
 
-// Add a new comment: create thread via REST then submit op via Socket.IO
+// Add a new comment: create thread via REST then submit comment op via existing socket
 async function addComment(
   projectId: string,
   docId: string,
@@ -415,6 +439,7 @@ async function addComment(
   content: string
 ): Promise<{ success: boolean; threadId?: string; message?: string }> {
   if (!overleafSessionCookie) return { success: false, message: 'not_logged_in' }
+  if (!overleafSock) return { success: false, message: 'not_connected' }
 
   // Generate a random threadId (24-char hex like Mongo ObjectId)
   const threadId = Array.from({ length: 24 }, () => Math.floor(Math.random() * 16).toString(16)).join('')
@@ -426,123 +451,29 @@ async function addComment(
   })
   if (!msgResult.ok) return { success: false, message: `REST failed: ${msgResult.status}` }
 
-  // Step 2: Submit the comment op via Socket.IO WebSocket
-  const hsRes = await overleafFetch(`/socket.io/1/?t=${Date.now()}&projectId=${projectId}`, { raw: true })
-  if (!hsRes.ok) return { success: false, message: 'handshake failed' }
-  const sid = (hsRes.data as string).split(':')[0]
-  if (!sid) return { success: false, message: 'no sid' }
-
-  const { session: electronSession } = await import('electron')
-  const ses = electronSession.fromPartition('overleaf-sio-add-' + Date.now())
-
-  ses.webRequest.onHeadersReceived((details, callback) => {
-    const headers = { ...details.responseHeaders }
-    delete headers['set-cookie']
-    delete headers['Set-Cookie']
-    callback({ responseHeaders: headers })
-  })
-
-  const allCookieParts = overleafSessionCookie.split('; ')
-  for (const sc of hsRes.setCookies) {
-    allCookieParts.push(sc.split(';')[0])
-  }
-  for (const pair of allCookieParts) {
-    const eqIdx = pair.indexOf('=')
-    if (eqIdx < 0) continue
-    try {
-      await ses.cookies.set({
-        url: 'https://www.overleaf.com',
-        name: pair.substring(0, eqIdx),
-        value: pair.substring(eqIdx + 1),
-        domain: '.overleaf.com',
-        path: '/',
-        secure: true
-      })
-    } catch { /* ignore */ }
-  }
-
-  const win = new BrowserWindow({
-    width: 800, height: 600, show: false,
-    webPreferences: { nodeIntegration: false, contextIsolation: false, session: ses }
-  })
-
+  // Step 2: Submit the comment op via the existing socket connection
   try {
-    win.webContents.on('console-message', (_e, _level, msg) => {
-      console.log('[overleaf-add-comment]', msg)
-    })
-    await win.loadURL('https://www.overleaf.com/login')
+    // Join doc if not already joined, to get the current version
+    const alreadyJoined = docEventHandlers.has(docId)
+    const joinResult = await overleafSock.joinDoc(docId)
+    const version = joinResult.version
 
-    const script = `
-      new Promise(async (mainResolve) => {
-        try {
-          var ws = new WebSocket('wss://' + location.host + '/socket.io/1/websocket/${sid}');
-          var ackId = 0, ackCbs = {}, evtCbs = {};
-
-          ws.onmessage = function(e) {
-            var d = e.data;
-            if (d === '2::') { ws.send('2::'); return; }
-            if (d === '1::') return;
-            var am = d.match(/^6:::(\\d+)\\+([\\s\\S]*)/);
-            if (am) {
-              var cb = ackCbs[parseInt(am[1])];
-              if (cb) { delete ackCbs[parseInt(am[1])]; try { cb(JSON.parse(am[2])); } catch(e2) { cb(null); } }
-              return;
-            }
-            var em2 = d.match(/^5:::(\\{[\\s\\S]*\\})/);
-            if (em2) {
-              try {
-                var evt = JSON.parse(em2[1]);
-                var ecb = evtCbs[evt.name];
-                if (ecb) { delete evtCbs[evt.name]; ecb(evt.args); }
-              } catch(e3) {}
-            }
-          };
+    // Send the comment op
+    const commentOp = { c: text, p: pos, t: threadId }
+    console.log('[addComment] submitting op:', JSON.stringify(commentOp), 'v:', version)
 
-          function emitAck(name, args) {
-            return new Promise(function(res) { ackId++; ackCbs[ackId] = res;
-              ws.send('5:' + ackId + '+::' + JSON.stringify({ name: name, args: args })); });
-          }
-          function waitEvent(name) {
-            return new Promise(function(res) { evtCbs[name] = res; });
-          }
+    await overleafSock.applyOtUpdate(docId, [commentOp], version, '')
+    console.log('[addComment] op applied successfully')
+
+    // Leave doc if we joined it just for this
+    if (!alreadyJoined) {
+      await overleafSock.leaveDoc(docId)
+    }
 
-          ws.onerror = function() { mainResolve({ error: 'ws_error' }); };
-          ws.onclose = function(ev) { console.log('ws closed: ' + ev.code); };
-
-          ws.onopen = async function() {
-            try {
-              var jpPromise = waitEvent('joinProjectResponse');
-              ws.send('5:::' + JSON.stringify({ name: 'joinProject', args: [{ project_id: '${projectId}' }] }));
-              await jpPromise;
-
-              // Join the doc to submit the op
-              await emitAck('joinDoc', ['${docId}']);
-
-              // Submit the comment op
-              var commentOp = { c: ${JSON.stringify(text)}, p: ${pos}, t: '${threadId}' };
-              console.log('submitting op: ' + JSON.stringify(commentOp));
-              await emitAck('applyOtUpdate', ['${docId}', { doc: '${docId}', op: [commentOp], v: 0 }]);
-
-              await emitAck('leaveDoc', ['${docId}']);
-              ws.close();
-              mainResolve({ success: true });
-            } catch (e) { ws.close(); mainResolve({ error: e.message }); }
-          };
-          setTimeout(function() { ws.close(); mainResolve({ error: 'timeout' }); }, 30000);
-        } catch (e) { mainResolve({ error: e.message }); }
-      });
-    `
-
-    const result = await win.webContents.executeJavaScript(script)
-    console.log('[overleaf] addComment result:', result)
-
-    if (result?.error) return { success: false, message: result.error }
     return { success: true, threadId }
   } catch (e) {
-    console.log('[overleaf] addComment error:', e)
+    console.log('[addComment] error:', e)
     return { success: false, message: String(e) }
-  } finally {
-    win.close()
   }
 }
 
@@ -663,6 +594,15 @@ ipcMain.handle('ot:connect', async (_e, projectId: string) => {
         sendToRenderer('cursor:remoteDisconnected', args[0])
       } else if (name === 'new-chat-message') {
         sendToRenderer('chat:newMessage', args[0])
+      } else if (
+        name === 'new-comment' ||
+        name === 'resolve-thread' ||
+        name === 'reopen-thread' ||
+        name === 'delete-thread' ||
+        name === 'edit-message' ||
+        name === 'delete-message'
+      ) {
+        sendToRenderer('comments:event', { type: name, args })
       }
     })
 
@@ -677,6 +617,107 @@ ipcMain.handle('ot:connect', async (_e, projectId: string) => {
     fileSyncBridge = new FileSyncBridge(overleafSock, tmpDir, docPathMap, pathDocMap, fileRefs, mainWindow!, projectId, overleafSessionCookie, overleafCsrfToken)
     await fileSyncBridge.start()
 
+    // Write MCP state + config for Claude Code integration
+    mcpStateDir = tmpDir
+    mcpProjectId = projectId
+    mcpCommentContexts = {}
+    mcpPathDocMap = pathDocMap
+    writeMcpState()
+    // Write .mcp.json so Claude Code auto-discovers the MCP server
+    const appRoot = app.isPackaged ? join(app.getAppPath(), '..') : join(__dirname, '..', '..')
+    const mcpServerPath = join(appRoot, 'src', 'mcp', 'lattex.mjs')
+    writeFile(join(tmpDir, '.mcp.json'), JSON.stringify({
+      mcpServers: {
+        lattex: {
+          command: 'node',
+          args: [mcpServerPath]
+        }
+      }
+    }, null, 2)).catch(() => {})
+    // Write CLAUDE.md with project context
+    writeFile(join(tmpDir, 'CLAUDE.md'), `# LatteX Project — Overleaf Integration
+
+This is a LaTeX project synced from Overleaf via LatteX. Files here are bidirectionally synced — edits you make will appear on Overleaf.
+
+## MCP Tools
+
+You have MCP tools to interact with Overleaf. Use them proactively.
+
+### Comments
+- **get_comments**: Read comments. Pass \`file\` to filter, \`include_resolved\` for all.
+- **resolve_comment**: Resolve a comment by \`thread_id\`.
+- **reopen_comment**: Reopen a resolved comment.
+- **reply_to_comment**: Reply to a comment thread.
+- **delete_comment**: Permanently delete a comment thread.
+
+### Chat
+- **get_chat_messages**: Read project chat history.
+- **send_chat_message**: Send a message to project chat.
+
+### Project
+- **list_project_files**: List all files with sizes.
+- **compile_latex**: Trigger LaTeX compilation. Pass \`main_file\` if needed.
+
+### Comment Workflow
+1. Use \`get_comments\` to see what reviewers have flagged
+2. Edit the .tex files to address the feedback
+3. Use \`reply_to_comment\` to explain what you changed
+4. Use \`resolve_comment\` to mark it as done
+`).catch(() => {})
+    // Write .claude/settings.json to auto-allow MCP tools
+    mkdirAsync(join(tmpDir, '.claude'), { recursive: true }).then(() =>
+      writeFile(join(tmpDir, '.claude', 'settings.json'), JSON.stringify({
+        permissions: {
+          allow: [
+            'mcp__lattex__get_comments',
+            'mcp__lattex__resolve_comment',
+            'mcp__lattex__reopen_comment',
+            'mcp__lattex__reply_to_comment',
+            'mcp__lattex__delete_comment',
+            'mcp__lattex__get_chat_messages',
+            'mcp__lattex__send_chat_message',
+            'mcp__lattex__list_project_files',
+            'mcp__lattex__compile_latex'
+          ]
+        }
+      }, null, 2))
+    ).catch(() => {})
+
+    // Fetch threads + comment contexts in background so editor highlights are correct from the start
+    setTimeout(async () => {
+      if (!overleafSock?.projectData) return
+
+      // Fetch threads (fast REST call) to know which are resolved
+      const threadResult = await overleafFetch(`/project/${projectId}/threads`)
+      if (threadResult.ok && threadResult.data) {
+        const threads = threadResult.data as Record<string, { resolved?: boolean }>
+        const resolvedIds: string[] = []
+        for (const [tid, t] of Object.entries(threads)) {
+          if (t.resolved) resolvedIds.push(tid)
+        }
+        sendToRenderer('comments:initThreads', { threads: threadResult.data, resolvedIds })
+      }
+
+      // Fetch comment contexts from all docs
+      const { docPathMap: dp } = walkRootFolder(overleafSock.projectData.project.rootFolder)
+      const contexts: Record<string, { file: string; text: string; pos: number }> = {}
+      for (const [did, rp] of Object.entries(dp)) {
+        try {
+          const alreadyJoined = docEventHandlers.has(did)
+          const result = await overleafSock.joinDoc(did)
+          if (result.ranges?.comments) {
+            for (const c of result.ranges.comments) {
+              if (c.op?.t) contexts[c.op.t] = { file: rp, text: c.op.c || '', pos: c.op.p || 0 }
+            }
+          }
+          if (!alreadyJoined) await overleafSock.leaveDoc(did)
+        } catch { /* ignore */ }
+      }
+      mcpCommentContexts = contexts
+      writeMcpState()
+      sendToRenderer('comments:initContexts', { contexts })
+    }, 3000)
+
     return {
       success: true,
       files,
@@ -697,6 +738,14 @@ ipcMain.handle('ot:connect', async (_e, projectId: string) => {
 })
 
 ipcMain.handle('ot:disconnect', async () => {
+  // Clean up MCP state file
+  if (mcpStateDir) {
+    unlink(join(mcpStateDir, '.lattex-mcp.json')).catch(() => {})
+  }
+  mcpStateDir = ''
+  mcpProjectId = ''
+  mcpCommentContexts = {}
+
   await fileSyncBridge?.stop()
   fileSyncBridge = null
   overleafSock?.disconnect()
@@ -1060,6 +1109,10 @@ ipcMain.handle('ot:fetchAllCommentContexts', async () => {
     }
   }
 
+  // Update MCP state with fresh comment contexts
+  mcpCommentContexts = contexts
+  writeMcpState()
+
   return { success: true, contexts }
 })
 
diff --git a/src/main/overleafProtocol.ts b/src/main/overleafProtocol.ts
index 884aff2..abee516 100644
--- a/src/main/overleafProtocol.ts
+++ b/src/main/overleafProtocol.ts
@@ -65,16 +65,21 @@ export function parseSocketMessage(raw: string): ParsedMessage | null {
       return null
     }
     case '6': {
-      // Ack: 6:::N+[jsonData]
-      const ackMatch = raw.match(/^6:::(\d+)\+([\s\S]*)/)
-      if (ackMatch) {
+      // Ack with data: 6:::N+[jsonData]
+      // Ack without data: 6:::N
+      const ackWithData = raw.match(/^6:::(\d+)\+([\s\S]*)/)
+      if (ackWithData) {
         try {
-          const data = JSON.parse(ackMatch[2])
-          return { type: 'ack', id: parseInt(ackMatch[1]), data }
+          const data = JSON.parse(ackWithData[2])
+          return { type: 'ack', id: parseInt(ackWithData[1]), data }
         } catch {
-          return { type: 'ack', id: parseInt(ackMatch[1]), data: null }
+          return { type: 'ack', id: parseInt(ackWithData[1]), data: null }
         }
       }
+      const ackNoData = raw.match(/^6:::(\d+)$/)
+      if (ackNoData) {
+        return { type: 'ack', id: parseInt(ackNoData[1]), data: null }
+      }
       return null
     }
     default:
diff --git a/src/main/overleafSocket.ts b/src/main/overleafSocket.ts
index 195eb05..96d9138 100644
--- a/src/main/overleafSocket.ts
+++ b/src/main/overleafSocket.ts
@@ -301,11 +301,8 @@ export class OverleafSocket extends EventEmitter {
     this.joinedDocs.delete(docId)
   }
 
-  async applyOtUpdate(docId: string, ops: unknown[], version: number, hash: string): Promise<void> {
-    // Use emitWithAck so the server's callback response comes back as a Socket.IO ack
-    // Do NOT send hash — Overleaf's document-updater hash check causes disconnect + rollback on mismatch
-    const result = await this.emitWithAck('applyOtUpdate', [docId, { doc: docId, op: ops, v: version }])
-    if (result) console.log(`[applyOtUpdate] ack for ${docId} v=${version}`)
+  async applyOtUpdate(docId: string, ops: unknown[], version: number, hash?: string): Promise<void> {
+    await this.emitWithAck('applyOtUpdate', [docId, { doc: docId, op: ops, v: version }])
   }
 
   /** Get list of connected users with their cursor positions */
diff --git a/src/mcp/lattex.mjs b/src/mcp/lattex.mjs
new file mode 100644
index 0000000..50c4a0e
--- /dev/null
+++ b/src/mcp/lattex.mjs
@@ -0,0 +1,560 @@
+#!/usr/bin/env node
+// Copyright (c) 2026 Yuren Hao
+// Licensed under AGPL-3.0 - see LICENSE file
+
+// MCP Server: LatteX
+// Provides tools for Claude Code to interact with the Overleaf project:
+// comments, chat, file listing, compilation
+
+import { Server } from '@modelcontextprotocol/sdk/server/index.js'
+import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'
+import {
+  CallToolRequestSchema,
+  ListToolsRequestSchema
+} from '@modelcontextprotocol/sdk/types.js'
+import { readFileSync, readdirSync, statSync } from 'fs'
+import { join, relative } from 'path'
+import https from 'https'
+
+// ── State ──────────────────────────────────────────────────────
+
+function readState() {
+  const cwd = process.cwd()
+  const statePath = join(cwd, '.lattex-mcp.json')
+  try {
+    return JSON.parse(readFileSync(statePath, 'utf-8'))
+  } catch {
+    throw new Error(
+      'Cannot read .lattex-mcp.json — is LatteX running and connected to an Overleaf project?'
+    )
+  }
+}
+
+// ── HTTP helper ────────────────────────────────────────────────
+
+function overleafRequest(method, path, cookie, csrf, body) {
+  return new Promise((resolve, reject) => {
+    const options = {
+      hostname: 'www.overleaf.com',
+      path,
+      method,
+      headers: {
+        Cookie: cookie,
+        Accept: 'application/json',
+        'User-Agent':
+          'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36'
+      }
+    }
+    if (body) {
+      options.headers['Content-Type'] = 'application/json'
+    }
+    if (csrf && method !== 'GET') {
+      options.headers['x-csrf-token'] = csrf
+    }
+
+    const req = https.request(options, (res) => {
+      let data = ''
+      res.on('data', (chunk) => (data += chunk))
+      res.on('end', () => {
+        let parsed
+        try {
+          parsed = JSON.parse(data)
+        } catch {
+          parsed = data
+        }
+        resolve({
+          ok: res.statusCode >= 200 && res.statusCode < 300,
+          status: res.statusCode,
+          data: parsed
+        })
+      })
+    })
+    req.on('error', reject)
+    if (body) req.write(JSON.stringify(body))
+    req.end()
+  })
+}
+
+// ── Helpers ────────────────────────────────────────────────────
+
+function fmtTime(ts) {
+  if (!ts) return ''
+  return new Date(ts).toLocaleString('en-US', {
+    month: 'short',
+    day: 'numeric',
+    hour: '2-digit',
+    minute: '2-digit'
+  })
+}
+
+function userName(user) {
+  if (!user) return ''
+  return [user.first_name, user.last_name].filter(Boolean).join(' ') ||
+    user.email?.split('@')[0] || ''
+}
+
+function textResult(text) {
+  return { content: [{ type: 'text', text }] }
+}
+
+function errorResult(text) {
+  return { content: [{ type: 'text', text }], isError: true }
+}
+
+// Walk a directory recursively and return relative paths
+function walkDir(dir, base) {
+  const results = []
+  try {
+    for (const entry of readdirSync(dir)) {
+      if (entry.startsWith('.')) continue
+      const full = join(dir, entry)
+      const rel = relative(base, full)
+      try {
+        const st = statSync(full)
+        if (st.isDirectory()) {
+          results.push({ path: rel + '/', size: 0, isDir: true })
+          results.push(...walkDir(full, base))
+        } else {
+          results.push({ path: rel, size: st.size, isDir: false })
+        }
+      } catch { /* skip */ }
+    }
+  } catch { /* skip */ }
+  return results
+}
+
+// ── Tool definitions ───────────────────────────────────────────
+
+const TOOLS = [
+  // ── Comments ──
+  {
+    name: 'get_comments',
+    description:
+      'Get unresolved Overleaf comments. Optionally filter by file path. Returns comment text, position, author, time, and thread_id for each comment.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        file: {
+          type: 'string',
+          description:
+            'Optional file path to filter comments (e.g. "latex/main.tex"). If omitted, returns all unresolved comments.'
+        },
+        include_resolved: {
+          type: 'boolean',
+          description: 'If true, also include resolved comments. Default: false.'
+        }
+      }
+    }
+  },
+  {
+    name: 'resolve_comment',
+    description: 'Resolve (close) an Overleaf comment thread by its thread_id.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        thread_id: {
+          type: 'string',
+          description: 'The thread_id of the comment to resolve.'
+        }
+      },
+      required: ['thread_id']
+    }
+  },
+  {
+    name: 'reopen_comment',
+    description: 'Reopen a previously resolved Overleaf comment thread.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        thread_id: {
+          type: 'string',
+          description: 'The thread_id of the comment to reopen.'
+        }
+      },
+      required: ['thread_id']
+    }
+  },
+  {
+    name: 'reply_to_comment',
+    description: 'Reply to an existing Overleaf comment thread.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        thread_id: {
+          type: 'string',
+          description: 'The thread_id to reply to.'
+        },
+        content: {
+          type: 'string',
+          description: 'The reply message content.'
+        }
+      },
+      required: ['thread_id', 'content']
+    }
+  },
+  {
+    name: 'delete_comment',
+    description: 'Delete an entire Overleaf comment thread and its highlight. This is permanent.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        thread_id: {
+          type: 'string',
+          description: 'The thread_id of the comment to delete.'
+        }
+      },
+      required: ['thread_id']
+    }
+  },
+  // ── Chat ──
+  {
+    name: 'get_chat_messages',
+    description: 'Get recent chat messages from the Overleaf project.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        limit: {
+          type: 'number',
+          description: 'Max number of messages to return. Default: 50.'
+        }
+      }
+    }
+  },
+  {
+    name: 'send_chat_message',
+    description: 'Send a message to the Overleaf project chat.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        content: {
+          type: 'string',
+          description: 'The message text to send.'
+        }
+      },
+      required: ['content']
+    }
+  },
+  // ── Project ──
+  {
+    name: 'list_project_files',
+    description: 'List all files in the synced project directory with their paths and sizes.',
+    inputSchema: {
+      type: 'object',
+      properties: {}
+    }
+  },
+  {
+    name: 'compile_latex',
+    description: 'Trigger LaTeX compilation of the project. Returns compilation status and log output.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        main_file: {
+          type: 'string',
+          description: 'Optional main .tex file path (e.g. "main.tex"). Uses project default if omitted.'
+        }
+      }
+    }
+  }
+]
+
+// ── Server ─────────────────────────────────────────────────────
+
+const server = new Server(
+  { name: 'lattex', version: '2.0.0' },
+  { capabilities: { tools: {} } }
+)
+
+server.setRequestHandler(ListToolsRequestSchema, async () => ({
+  tools: TOOLS
+}))
+
+server.setRequestHandler(CallToolRequestSchema, async (request) => {
+  const { name, arguments: args } = request.params
+
+  try {
+    const state = readState()
+    const { projectId, cookie, csrf, commentContexts, pathDocMap } = state
+
+    switch (name) {
+      // ── Comments ──────────────────────────────────
+
+      case 'get_comments': {
+        const filterFile = args?.file || null
+        const includeResolved = args?.include_resolved || false
+
+        const result = await overleafRequest(
+          'GET',
+          `/project/${projectId}/threads`,
+          cookie,
+          csrf
+        )
+        if (!result.ok) {
+          return errorResult(`Failed to fetch comments: HTTP ${result.status}`)
+        }
+
+        const threads = result.data
+        const lines = []
+
+        for (const [threadId, thread] of Object.entries(threads)) {
+          if (!includeResolved && thread.resolved) continue
+          const ctx = commentContexts?.[threadId]
+          if (!ctx) continue
+          if (filterFile && ctx.file !== filterFile) continue
+
+          const firstMsg = thread.messages?.[0]
+          if (!firstMsg) continue
+
+          const author = userName(firstMsg.user)
+          const time = fmtTime(firstMsg.timestamp)
+          const attribution = [author, time].filter(Boolean).join(', ')
+          const status = thread.resolved ? ' [RESOLVED]' : ''
+
+          let entry = `Thread ${threadId}${status}:\n  File: ${ctx.file}\n  Position: ${ctx.pos}\n  Highlighted text: "${ctx.text}"\n  Comment: "${firstMsg.content}"${attribution ? ` — ${attribution}` : ''}`
+
+          for (let i = 1; i < thread.messages.length; i++) {
+            const reply = thread.messages[i]
+            const rAuthor = userName(reply.user)
+            const rTime = fmtTime(reply.timestamp)
+            const rAttr = [rAuthor, rTime].filter(Boolean).join(', ')
+            entry += `\n  Reply: "${reply.content}"${rAttr ? ` — ${rAttr}` : ''}`
+          }
+
+          lines.push(entry)
+        }
+
+        if (lines.length === 0) {
+          return textResult(
+            filterFile
+              ? `No ${includeResolved ? '' : 'unresolved '}comments in ${filterFile}.`
+              : `No ${includeResolved ? '' : 'unresolved '}comments.`
+          )
+        }
+
+        return textResult(
+          `${lines.length} comment(s):\n\n${lines.join('\n\n')}`
+        )
+      }
+
+      case 'resolve_comment': {
+        const threadId = args.thread_id
+        const ctx = commentContexts?.[threadId]
+        const docId = ctx ? pathDocMap?.[ctx.file] : null
+        const docSegment = docId ? `/doc/${docId}` : ''
+        const result = await overleafRequest(
+          'POST',
+          `/project/${projectId}${docSegment}/thread/${threadId}/resolve`,
+          cookie,
+          csrf,
+          {}
+        )
+        return textResult(
+          result.ok
+            ? `Comment ${threadId} resolved.`
+            : `Failed to resolve: HTTP ${result.status}`
+        )
+      }
+
+      case 'reopen_comment': {
+        const threadId = args.thread_id
+        const ctx = commentContexts?.[threadId]
+        const docId = ctx ? pathDocMap?.[ctx.file] : null
+        const docSegment = docId ? `/doc/${docId}` : ''
+        const result = await overleafRequest(
+          'POST',
+          `/project/${projectId}${docSegment}/thread/${threadId}/reopen`,
+          cookie,
+          csrf,
+          {}
+        )
+        return textResult(
+          result.ok
+            ? `Comment ${threadId} reopened.`
+            : `Failed to reopen: HTTP ${result.status}`
+        )
+      }
+
+      case 'reply_to_comment': {
+        const { thread_id: threadId, content } = args
+        const result = await overleafRequest(
+          'POST',
+          `/project/${projectId}/thread/${threadId}/messages`,
+          cookie,
+          csrf,
+          { content }
+        )
+        return textResult(
+          result.ok
+            ? `Replied to thread ${threadId}.`
+            : `Failed to reply: HTTP ${result.status}`
+        )
+      }
+
+      case 'delete_comment': {
+        const threadId = args.thread_id
+        const ctx = commentContexts?.[threadId]
+        const docId = ctx ? pathDocMap?.[ctx.file] : null
+        if (!docId) {
+          return errorResult(`Cannot delete: no doc found for thread ${threadId}`)
+        }
+        const result = await overleafRequest(
+          'DELETE',
+          `/project/${projectId}/doc/${docId}/thread/${threadId}`,
+          cookie,
+          csrf
+        )
+        return textResult(
+          result.ok
+            ? `Comment ${threadId} deleted.`
+            : `Failed to delete: HTTP ${result.status}`
+        )
+      }
+
+      // ── Chat ──────────────────────────────────────
+
+      case 'get_chat_messages': {
+        const limit = args?.limit || 50
+        const result = await overleafRequest(
+          'GET',
+          `/project/${projectId}/messages?limit=${limit}`,
+          cookie,
+          csrf
+        )
+        if (!result.ok) {
+          return errorResult(`Failed to fetch chat: HTTP ${result.status}`)
+        }
+
+        const messages = result.data
+        if (!Array.isArray(messages) || messages.length === 0) {
+          return textResult('No chat messages.')
+        }
+
+        const lines = messages.map((msg) => {
+          const author = userName(msg.user)
+          const time = fmtTime(msg.timestamp)
+          const attr = [author, time].filter(Boolean).join(', ')
+          return `${attr ? `[${attr}] ` : ''}${msg.content}`
+        })
+
+        // Messages come newest-first from API, reverse for chronological
+        lines.reverse()
+
+        return textResult(
+          `${messages.length} chat message(s):\n\n${lines.join('\n')}`
+        )
+      }
+
+      case 'send_chat_message': {
+        const { content } = args
+        const result = await overleafRequest(
+          'POST',
+          `/project/${projectId}/messages`,
+          cookie,
+          csrf,
+          { content }
+        )
+        return textResult(
+          result.ok
+            ? 'Message sent.'
+            : `Failed to send: HTTP ${result.status}`
+        )
+      }
+
+      // ── Project ───────────────────────────────────
+
+      case 'list_project_files': {
+        const cwd = process.cwd()
+        const files = walkDir(cwd, cwd)
+          .filter(f => !f.path.startsWith('.'))
+
+        if (files.length === 0) {
+          return textResult('No files found in project directory.')
+        }
+
+        const lines = files.map(f => {
+          if (f.isDir) return `📁 ${f.path}`
+          const sizeKb = (f.size / 1024).toFixed(1)
+          return `   ${f.path} (${sizeKb} KB)`
+        })
+
+        return textResult(
+          `${files.filter(f => !f.isDir).length} files in project:\n\n${lines.join('\n')}`
+        )
+      }
+
+      case 'compile_latex': {
+        // Compilation happens via the LatteX app's local LaTeX installation
+        // We trigger it by writing a signal file that the app watches,
+        // or we can call the Overleaf compile endpoint
+        const mainFile = args?.main_file || null
+
+        // Use Overleaf's server-side compilation
+        const body = {
+          check: 'silent',
+          draft: false,
+          incrementalCompilesEnabled: true,
+          rootDoc_id: null,
+          stopOnFirstError: false
+        }
+
+        // If a specific main file is given, find its docId
+        if (mainFile && pathDocMap) {
+          const docId = pathDocMap[mainFile]
+          if (docId) body.rootDoc_id = docId
+        }
+
+        const result = await overleafRequest(
+          'POST',
+          `/project/${projectId}/compile`,
+          cookie,
+          csrf,
+          body
+        )
+
+        if (!result.ok) {
+          return errorResult(`Compilation request failed: HTTP ${result.status}`)
+        }
+
+        const compileData = result.data
+        const status = compileData?.status || 'unknown'
+
+        if (status === 'success') {
+          return textResult('Compilation successful.')
+        } else if (status === 'failure' || status === 'error') {
+          // Try to extract error info from output files
+          const outputFiles = compileData?.outputFiles || []
+          const logFile = outputFiles.find(f => f.path === 'output.log')
+          if (logFile) {
+            // Fetch the log
+            const logUrl = `/project/${projectId}/output/${logFile.path}?build=${logFile.build}`
+            const logResult = await overleafRequest('GET', logUrl, cookie, csrf)
+            if (logResult.ok && typeof logResult.data === 'string') {
+              // Extract just the error lines
+              const logLines = logResult.data.split('\n')
+              const errorLines = logLines.filter(l =>
+                l.startsWith('!') || l.includes('Error') || l.includes('error')
+              ).slice(0, 20)
+
+              return textResult(
+                `Compilation failed.\n\nErrors:\n${errorLines.join('\n') || 'See full log for details.'}`
+              )
+            }
+          }
+          return textResult(`Compilation failed with status: ${status}`)
+        } else {
+          return textResult(`Compilation status: ${status}`)
+        }
+      }
+
+      default:
+        return errorResult(`Unknown tool: ${name}`)
+    }
+  } catch (e) {
+    return errorResult(`Error: ${e.message}`)
+  }
+})
+
+// ── Start ──────────────────────────────────────────────────────
+
+const transport = new StdioServerTransport()
+await server.connect(transport)
diff --git a/src/preload/index.ts b/src/preload/index.ts
index 7b23d27..2be6e0b 100644
--- a/src/preload/index.ts
+++ b/src/preload/index.ts
@@ -43,10 +43,10 @@ const api = {
     ipcRenderer.invoke('overleaf:getThreads', projectId) as Promise<{ success: boolean; threads?: Record<string, unknown>; message?: string }>,
   overleafReplyThread: (projectId: string, threadId: string, content: string) =>
     ipcRenderer.invoke('overleaf:replyThread', projectId, threadId, content) as Promise<{ success: boolean }>,
-  overleafResolveThread: (projectId: string, threadId: string) =>
-    ipcRenderer.invoke('overleaf:resolveThread', projectId, threadId) as Promise<{ success: boolean }>,
-  overleafReopenThread: (projectId: string, threadId: string) =>
-    ipcRenderer.invoke('overleaf:reopenThread', projectId, threadId) as Promise<{ success: boolean }>,
+  overleafResolveThread: (projectId: string, threadId: string, docId?: string) =>
+    ipcRenderer.invoke('overleaf:resolveThread', projectId, threadId, docId) as Promise<{ success: boolean }>,
+  overleafReopenThread: (projectId: string, threadId: string, docId?: string) =>
+    ipcRenderer.invoke('overleaf:reopenThread', projectId, threadId, docId) as Promise<{ success: boolean }>,
   overleafDeleteMessage: (projectId: string, threadId: string, messageId: string) =>
     ipcRenderer.invoke('overleaf:deleteMessage', projectId, threadId, messageId) as Promise<{ success: boolean }>,
   overleafEditMessage: (projectId: string, threadId: string, messageId: string, content: string) =>
@@ -182,6 +182,23 @@ const api = {
     return () => ipcRenderer.removeListener('chat:newMessage', handler)
   },
 
+  // Comments real-time events
+  onCommentsEvent: (cb: (event: { type: string; args: unknown[] }) => void) => {
+    const handler = (_e: Electron.IpcRendererEvent, event: { type: string; args: unknown[] }) => cb(event)
+    ipcRenderer.on('comments:event', handler)
+    return () => ipcRenderer.removeListener('comments:event', handler)
+  },
+  onCommentsInitThreads: (cb: (data: { threads: Record<string, unknown>; resolvedIds: string[] }) => void) => {
+    const handler = (_e: Electron.IpcRendererEvent, data: { threads: Record<string, unknown>; resolvedIds: string[] }) => cb(data)
+    ipcRenderer.on('comments:initThreads', handler)
+    return () => ipcRenderer.removeListener('comments:initThreads', handler)
+  },
+  onCommentsInitContexts: (cb: (data: { contexts: Record<string, { file: string; text: string; pos: number }> }) => void) => {
+    const handler = (_e: Electron.IpcRendererEvent, data: { contexts: Record<string, { file: string; text: string; pos: number }> }) => cb(data)
+    ipcRenderer.on('comments:initContexts', handler)
+    return () => ipcRenderer.removeListener('comments:initContexts', handler)
+  },
+
   // Shell
   openExternal: (url: string) => ipcRenderer.invoke('shell:openExternal', url),
   showInFinder: (path: string) => ipcRenderer.invoke('shell:showInFinder', path)
diff --git a/src/renderer/src/App.css b/src/renderer/src/App.css
index aae0b4b..a6a4003 100644
--- a/src/renderer/src/App.css
+++ b/src/renderer/src/App.css
@@ -1465,10 +1465,14 @@ html, body, #root {
   min-width: 280px;
   height: 100%;
   border-left: 1px solid var(--border);
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
 }
 
 .review-panel {
-  height: 100%;
+  flex: 1;
+  min-height: 0;
   display: flex;
   flex-direction: column;
   background: var(--bg-primary);
@@ -1812,17 +1816,6 @@ html, body, #root {
   gap: 4px;
 }
 
-.terminal-toolbar .pdf-tab {
-  color: #A09880;
-}
-.terminal-toolbar .pdf-tab:hover {
-  color: #C8BFA0;
-}
-.terminal-toolbar .pdf-tab.active {
-  background: #3D3830;
-  color: #E8DFC0;
-}
-
 .terminal-content {
   flex: 1;
   padding: 4px;
@@ -1850,6 +1843,68 @@ html, body, #root {
   color: #E8DFC0 !important;
 }
 
+.terminal-tab-bar {
+  display: flex;
+  align-items: center;
+  height: 28px;
+  background: #1E1B15;
+  border-top: 1px solid #3D3830;
+  padding: 0 4px;
+  gap: 2px;
+  flex-shrink: 0;
+}
+
+.terminal-tab {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  padding: 2px 10px;
+  font-size: 11px;
+  color: #8B7D5E;
+  cursor: pointer;
+  border-radius: 4px;
+  user-select: none;
+}
+.terminal-tab:hover {
+  color: #C8BFA0;
+  background: #2D2A24;
+}
+.terminal-tab.active {
+  color: #E8DFC0;
+  background: #3D3830;
+}
+
+.terminal-tab-close {
+  font-size: 13px;
+  line-height: 1;
+  opacity: 0;
+  cursor: pointer;
+  padding: 0 2px;
+  border-radius: 2px;
+}
+.terminal-tab:hover .terminal-tab-close {
+  opacity: 0.6;
+}
+.terminal-tab-close:hover {
+  opacity: 1 !important;
+  background: #5C5040;
+}
+
+.terminal-tab-add {
+  background: none;
+  border: none;
+  color: #6B5B3E;
+  font-size: 16px;
+  cursor: pointer;
+  padding: 0 6px;
+  line-height: 1;
+  border-radius: 4px;
+}
+.terminal-tab-add:hover {
+  color: #E8DFC0;
+  background: #2D2A24;
+}
+
 /* ── Status Bar ──────────────────────────────────────────────── */
 
 .status-bar {
diff --git a/src/renderer/src/App.tsx b/src/renderer/src/App.tsx
index 82306c9..ca2fc1e 100644
--- a/src/renderer/src/App.tsx
+++ b/src/renderer/src/App.tsx
@@ -111,6 +111,15 @@ export default function App() {
       }
     })
 
+    // Listen for initial comment data (threads + contexts) from background fetch on connect
+    const unsubInitThreads = window.api.onCommentsInitThreads?.((data) => {
+      const store = useAppStore.getState()
+      store.setResolvedThreadIds(new Set(data.resolvedIds))
+    })
+    const unsubInitContexts = window.api.onCommentsInitContexts?.((data) => {
+      useAppStore.getState().setCommentContexts(data.contexts)
+    })
+
     // Listen for remote cursor updates
     const unsubCursorUpdate = window.api.onCursorRemoteUpdate((raw) => {
       const data = raw as {
@@ -168,6 +177,8 @@ export default function App() {
       unsubRejoined()
       unsubExternalEdit()
       unsubNewDoc()
+      unsubInitThreads?.()
+      unsubInitContexts?.()
       unsubCursorUpdate()
       unsubCursorDisconnected()
       remoteCursors.clear()
diff --git a/src/renderer/src/components/Editor.tsx b/src/renderer/src/components/Editor.tsx
index 75b3872..4252464 100644
--- a/src/renderer/src/components/Editor.tsx
+++ b/src/renderer/src/components/Editor.tsx
@@ -79,6 +79,7 @@ export default function Editor() {
 
   const pendingGoTo = useAppStore((s) => s.pendingGoTo)
   const commentContexts = useAppStore((s) => s.commentContexts)
+  const resolvedThreadIds = useAppStore((s) => s.resolvedThreadIds)
   const hoveredThreadId = useAppStore((s) => s.hoveredThreadId)
   const overleafProjectId = useAppStore((s) => s.overleafProjectId)
   const pathDocMap = useAppStore((s) => s.pathDocMap)
@@ -118,10 +119,18 @@ export default function Editor() {
     )
     setSubmittingComment(false)
     if (result.success) {
+      // Add context immediately so highlight + review panel update without re-fetch
+      if (result.threadId && activeTab) {
+        const store = useAppStore.getState()
+        store.setCommentContexts({
+          ...store.commentContexts,
+          [result.threadId]: { file: activeTab, text: newComment.text, pos: newComment.from }
+        })
+      }
       setNewComment(null)
       setCommentInput('')
     }
-  }, [newComment, commentInput, overleafProjectId, getDocIdForFile])
+  }, [newComment, commentInput, overleafProjectId, activeTab, getDocIdForFile])
 
   // Handle goTo when file is already open
   useEffect(() => {
@@ -325,12 +334,12 @@ export default function Editor() {
     }
   }, [activeTab, pathDocMap])
 
-  // Sync comment ranges to CodeMirror
+  // Sync comment ranges to CodeMirror (exclude resolved threads)
   useEffect(() => {
     if (!viewRef.current || !activeTab) return
     const ranges: CommentRange[] = []
     for (const [threadId, ctx] of Object.entries(commentContexts)) {
-      if (ctx.file === activeTab && ctx.text) {
+      if (ctx.file === activeTab && ctx.text && !resolvedThreadIds.has(threadId)) {
         ranges.push({
           threadId,
           from: ctx.pos,
@@ -340,7 +349,7 @@ export default function Editor() {
       }
     }
     viewRef.current.dispatch({ effects: setCommentRangesEffect.of(ranges) })
-  }, [commentContexts, activeTab])
+  }, [commentContexts, activeTab, resolvedThreadIds])
 
   // Sync hover state
   useEffect(() => {
diff --git a/src/renderer/src/components/ReviewPanel.tsx b/src/renderer/src/components/ReviewPanel.tsx
index 7edac50..7e6c9e5 100644
--- a/src/renderer/src/components/ReviewPanel.tsx
+++ b/src/renderer/src/components/ReviewPanel.tsx
@@ -45,24 +45,36 @@ export default function ReviewPanel() {
   const [editText, setEditText] = useState('')
   const threadRefs = useRef<Record<string, HTMLDivElement | null>>({})
 
+  // Initial fetch — threads from REST, contexts only if not cached
   const fetchThreads = useCallback(async () => {
     if (!overleafProjectId) return
     setLoading(true)
     setError('')
 
-    const [threadResult, ctxResult] = await Promise.all([
-      window.api.overleafGetThreads(overleafProjectId),
-      window.api.otFetchAllCommentContexts()
-    ])
+    const hasContexts = Object.keys(useAppStore.getState().commentContexts).length > 0
 
+    const threadPromise = window.api.overleafGetThreads(overleafProjectId)
+    const ctxPromise = !hasContexts ? window.api.otFetchAllCommentContexts() : null
+
+    const threadResult = await threadPromise
     setLoading(false)
     if (threadResult.success && threadResult.threads) {
-      setThreads(threadResult.threads as ThreadMap)
+      const tm = threadResult.threads as ThreadMap
+      setThreads(tm)
+      const resolved = new Set<string>()
+      for (const [tid, t] of Object.entries(tm)) {
+        if (t.resolved) resolved.add(tid)
+      }
+      useAppStore.getState().setResolvedThreadIds(resolved)
     } else {
       setError(threadResult.message || 'Failed to fetch comments')
     }
-    if (ctxResult.success && ctxResult.contexts) {
-      useAppStore.getState().setCommentContexts(ctxResult.contexts)
+
+    if (ctxPromise) {
+      const ctxResult = await ctxPromise
+      if (ctxResult.success && ctxResult.contexts) {
+        useAppStore.getState().setCommentContexts(ctxResult.contexts)
+      }
     }
   }, [overleafProjectId])
 
@@ -70,38 +82,188 @@ export default function ReviewPanel() {
     fetchThreads()
   }, [fetchThreads])
 
+  // Handle real-time comment events from Overleaf socket — update state locally
+  useEffect(() => {
+    if (!window.api.onCommentsEvent) return
+    return window.api.onCommentsEvent((event) => {
+      const { type, args } = event
+      switch (type) {
+        case 'new-comment': {
+          const threadId = args[0] as string
+          const comment = args[1] as Message
+          setThreads(prev => {
+            if (prev[threadId]) {
+              // Reply to existing thread
+              return {
+                ...prev,
+                [threadId]: {
+                  ...prev[threadId],
+                  messages: [...prev[threadId].messages, comment]
+                }
+              }
+            }
+            // New thread — add it
+            return { ...prev, [threadId]: { messages: [comment] } }
+          })
+          break
+        }
+        case 'resolve-thread': {
+          const threadId = args[0] as string
+          const user = args[1] as User | undefined
+          setThreads(prev => {
+            if (!prev[threadId]) return prev
+            return {
+              ...prev,
+              [threadId]: {
+                ...prev[threadId],
+                resolved: true,
+                resolved_by_user: user,
+                resolved_at: new Date().toISOString()
+              }
+            }
+          })
+          const store = useAppStore.getState()
+          store.setResolvedThreadIds(new Set([...store.resolvedThreadIds, threadId]))
+          break
+        }
+        case 'reopen-thread': {
+          const threadId = args[0] as string
+          setThreads(prev => {
+            if (!prev[threadId]) return prev
+            const t = { ...prev[threadId] }
+            delete t.resolved
+            delete t.resolved_by_user
+            delete t.resolved_at
+            return { ...prev, [threadId]: t }
+          })
+          const store = useAppStore.getState()
+          const ids = new Set(store.resolvedThreadIds)
+          ids.delete(threadId)
+          store.setResolvedThreadIds(ids)
+          break
+        }
+        case 'delete-thread': {
+          const threadId = args[0] as string
+          setThreads(prev => {
+            const next = { ...prev }
+            delete next[threadId]
+            return next
+          })
+          // Remove context so highlight disappears
+          const store = useAppStore.getState()
+          const newCtx = { ...store.commentContexts }
+          delete newCtx[threadId]
+          store.setCommentContexts(newCtx)
+          const ids = new Set(store.resolvedThreadIds)
+          ids.delete(threadId)
+          store.setResolvedThreadIds(ids)
+          break
+        }
+        case 'edit-message': {
+          const threadId = args[0] as string
+          const messageId = args[1] as string
+          const content = args[2] as string
+          setThreads(prev => {
+            if (!prev[threadId]) return prev
+            return {
+              ...prev,
+              [threadId]: {
+                ...prev[threadId],
+                messages: prev[threadId].messages.map(m =>
+                  m.id === messageId ? { ...m, content } : m
+                )
+              }
+            }
+          })
+          break
+        }
+        case 'delete-message': {
+          const threadId = args[0] as string
+          const messageId = args[1] as string
+          setThreads(prev => {
+            if (!prev[threadId]) return prev
+            return {
+              ...prev,
+              [threadId]: {
+                ...prev[threadId],
+                messages: prev[threadId].messages.filter(m => m.id !== messageId)
+              }
+            }
+          })
+          break
+        }
+      }
+    })
+  }, [])
+
   useEffect(() => {
     if (!focusedThreadId) return
     const el = threadRefs.current[focusedThreadId]
     if (el) el.scrollIntoView({ behavior: 'smooth', block: 'nearest' })
   }, [focusedThreadId])
 
+  // --- Local actions: optimistic updates, no REST re-fetch ---
+
   const handleReply = async (threadId: string) => {
     if (!replyText.trim() || !overleafProjectId) return
-    const result = await window.api.overleafReplyThread(overleafProjectId, threadId, replyText.trim())
-    if (result.success) {
-      setReplyText('')
-      setReplyingTo(null)
-      fetchThreads()
-    }
+    const content = replyText.trim()
+    setReplyText('')
+    setReplyingTo(null)
+    // Server will broadcast new-comment event which updates state
+    await window.api.overleafReplyThread(overleafProjectId, threadId, content)
+  }
+
+  const getDocIdForThread = (threadId: string): string | undefined => {
+    const ctx = contexts[threadId]
+    if (!ctx) return undefined
+    const { pathDocMap } = useAppStore.getState()
+    return pathDocMap[ctx.file]
   }
 
   const handleResolve = async (threadId: string) => {
     if (!overleafProjectId) return
-    await window.api.overleafResolveThread(overleafProjectId, threadId)
-    fetchThreads()
+    // Optimistic: mark resolved immediately
+    setThreads(prev => {
+      if (!prev[threadId]) return prev
+      return { ...prev, [threadId]: { ...prev[threadId], resolved: true, resolved_at: new Date().toISOString() } }
+    })
+    const store = useAppStore.getState()
+    store.setResolvedThreadIds(new Set([...store.resolvedThreadIds, threadId]))
+    await window.api.overleafResolveThread(overleafProjectId, threadId, getDocIdForThread(threadId))
   }
 
   const handleReopen = async (threadId: string) => {
     if (!overleafProjectId) return
-    await window.api.overleafReopenThread(overleafProjectId, threadId)
-    fetchThreads()
+    // Optimistic: mark unresolved immediately
+    setThreads(prev => {
+      if (!prev[threadId]) return prev
+      const t = { ...prev[threadId] }
+      delete t.resolved
+      delete t.resolved_by_user
+      delete t.resolved_at
+      return { ...prev, [threadId]: t }
+    })
+    const store = useAppStore.getState()
+    const ids = new Set(store.resolvedThreadIds)
+    ids.delete(threadId)
+    store.setResolvedThreadIds(ids)
+    await window.api.overleafReopenThread(overleafProjectId, threadId, getDocIdForThread(threadId))
   }
 
   const handleDeleteMessage = async (threadId: string, messageId: string) => {
     if (!overleafProjectId) return
+    // Optimistic: remove message immediately
+    setThreads(prev => {
+      if (!prev[threadId]) return prev
+      return {
+        ...prev,
+        [threadId]: {
+          ...prev[threadId],
+          messages: prev[threadId].messages.filter(m => m.id !== messageId)
+        }
+      }
+    })
     await window.api.overleafDeleteMessage(overleafProjectId, threadId, messageId)
-    fetchThreads()
   }
 
   const handleStartEdit = (threadId: string, msg: Message) => {
@@ -111,25 +273,51 @@ export default function ReviewPanel() {
 
   const handleSaveEdit = async () => {
     if (!editingMsg || !editText.trim() || !overleafProjectId) return
-    await window.api.overleafEditMessage(overleafProjectId, editingMsg.threadId, editingMsg.messageId, editText.trim())
+    const { threadId, messageId } = editingMsg
+    const content = editText.trim()
+    // Optimistic: update message immediately
+    setThreads(prev => {
+      if (!prev[threadId]) return prev
+      return {
+        ...prev,
+        [threadId]: {
+          ...prev[threadId],
+          messages: prev[threadId].messages.map(m =>
+            m.id === messageId ? { ...m, content } : m
+          )
+        }
+      }
+    })
     setEditingMsg(null)
     setEditText('')
-    fetchThreads()
+    await window.api.overleafEditMessage(overleafProjectId, threadId, messageId, content)
   }
 
   const handleDeleteThread = async (threadId: string) => {
     if (!overleafProjectId) return
     const ctx = contexts[threadId]
     const store = useAppStore.getState()
+
+    // Optimistic: remove thread, context, and highlight immediately
+    setThreads(prev => {
+      const next = { ...prev }
+      delete next[threadId]
+      return next
+    })
+    const newCtx = { ...store.commentContexts }
+    delete newCtx[threadId]
+    store.setCommentContexts(newCtx)
+    const ids = new Set(store.resolvedThreadIds)
+    ids.delete(threadId)
+    store.setResolvedThreadIds(ids)
+
     if (ctx) {
       const docId = store.pathDocMap[ctx.file]
       if (docId) {
         await window.api.overleafDeleteThread(overleafProjectId, docId, threadId)
-        fetchThreads()
         return
       }
     }
-    fetchThreads()
   }
 
   const getUserName = (msg: Message) => {
@@ -137,7 +325,7 @@ export default function ReviewPanel() {
       return msg.user.last_name ? `${msg.user.first_name} ${msg.user.last_name}` : msg.user.first_name
     }
     if (msg.user?.email) return msg.user.email.split('@')[0]
-    return msg.user_id.slice(-6)
+    return msg.user_id?.slice(-6) || '?'
   }
 
   const formatTime = (ts: number) => {
@@ -154,12 +342,10 @@ export default function ReviewPanel() {
     return d.toLocaleDateString()
   }
 
-  // Navigate to comment position — always works for current file since it's already open
   const handleClickContext = (threadId: string) => {
     const ctx = contexts[threadId]
     if (!ctx) return
     const store = useAppStore.getState()
-    // File should already be open since we only show current file's comments
     store.setPendingGoTo({ file: ctx.file, pos: ctx.pos, highlight: ctx.text })
   }
 
@@ -172,7 +358,6 @@ export default function ReviewPanel() {
     )
   }
 
-  // Filter threads to only show ones belonging to the current file
   const threadEntries = Object.entries(threads)
   const fileThreads = activeTab
     ? threadEntries.filter(([threadId]) => {
diff --git a/src/renderer/src/components/Terminal.tsx b/src/renderer/src/components/Terminal.tsx
index bc29633..ea54343 100644
--- a/src/renderer/src/components/Terminal.tsx
+++ b/src/renderer/src/components/Terminal.tsx
@@ -124,39 +124,78 @@ function TerminalInstance({ id, cwd, cmd, args, visible }: {
   )
 }
 
+interface TabInfo {
+  id: string
+  name: string
+}
+
+let nextTabId = 0
+
 export default function Terminal() {
-  const [mode, setMode] = useState<'terminal' | 'claude'>('terminal')
-  const [claudeSpawned, setClaudeSpawned] = useState(false)
+  const [tabs, setTabs] = useState<TabInfo[]>(() => [
+    { id: `term-${++nextTabId}`, name: 'Terminal' }
+  ])
+  const [activeTabId, setActiveTabId] = useState(() => `term-${nextTabId}`)
   const syncDir = useAppStore((s) => s.syncDir) || '/tmp'
 
-  const launchClaude = useCallback(() => {
-    setClaudeSpawned(true)
-    setMode('claude')
+  const addTab = useCallback(() => {
+    const id = `term-${++nextTabId}`
+    setTabs((prev) => {
+      const name = `Terminal ${prev.length + 1}`
+      return [...prev, { id, name }]
+    })
+    setActiveTabId(id)
   }, [])
 
+  const closeTab = useCallback((tabId: string) => {
+    setTabs((prev) => {
+      if (prev.length <= 1) return prev
+      const idx = prev.findIndex((t) => t.id === tabId)
+      const next = prev.filter((t) => t.id !== tabId)
+      // If closing the active tab, switch to adjacent
+      if (tabId === activeTabId) {
+        const newIdx = Math.min(idx, next.length - 1)
+        setActiveTabId(next[newIdx].id)
+      }
+      return next
+    })
+  }, [activeTabId])
+
   return (
     <div className="terminal-panel">
       <div className="terminal-toolbar">
-        <button
-          className={`pdf-tab ${mode === 'terminal' ? 'active' : ''}`}
-          onClick={() => setMode('terminal')}
-        >
-          Terminal
-        </button>
-        <button
-          className={`pdf-tab ${mode === 'claude' ? 'active' : ''}`}
-          onClick={launchClaude}
-        >
-          Claude
-        </button>
-        <div className="pdf-toolbar-spacer" />
-        <QuickActions ptyId={claudeSpawned ? 'claude' : 'terminal'} />
+        <QuickActions ptyId={activeTabId} />
       </div>
 
-      <TerminalInstance id="terminal" cwd={syncDir} visible={mode === 'terminal'} />
-      {claudeSpawned && (
-        <TerminalInstance id="claude" cwd={syncDir} args={['-l', '-c', 'claude']} visible={mode === 'claude'} />
-      )}
+      {tabs.map((tab) => (
+        <TerminalInstance
+          key={tab.id}
+          id={tab.id}
+          cwd={syncDir}
+          visible={tab.id === activeTabId}
+        />
+      ))}
+
+      <div className="terminal-tab-bar">
+        {tabs.map((tab) => (
+          <div
+            key={tab.id}
+            className={`terminal-tab ${tab.id === activeTabId ? 'active' : ''}`}
+            onClick={() => setActiveTabId(tab.id)}
+          >
+            <span className="terminal-tab-name">{tab.name}</span>
+            {tabs.length > 1 && (
+              <span
+                className="terminal-tab-close"
+                onClick={(e) => { e.stopPropagation(); closeTab(tab.id) }}
+              >
+                ×
+              </span>
+            )}
+          </div>
+        ))}
+        <button className="terminal-tab-add" onClick={addTab}>+</button>
+      </div>
     </div>
   )
 }
diff --git a/src/renderer/src/stores/appStore.ts b/src/renderer/src/stores/appStore.ts
index e9c47ed..ff56c28 100644
--- a/src/renderer/src/stores/appStore.ts
+++ b/src/renderer/src/stores/appStore.ts
@@ -109,6 +109,8 @@ interface AppState {
   // Comment data
   commentContexts: Record<string, CommentContext>
   setCommentContexts: (c: Record<string, CommentContext>) => void
+  resolvedThreadIds: Set<string>
+  setResolvedThreadIds: (ids: Set<string>) => void
   overleafDocs: Record<string, string>
   setOverleafDocs: (d: Record<string, string>) => void
   hoveredThreadId: string | null
@@ -219,6 +221,8 @@ export const useAppStore = create<AppState>((set) => ({
 
   commentContexts: {},
   setCommentContexts: (c) => set({ commentContexts: c }),
+  resolvedThreadIds: new Set<string>(),
+  setResolvedThreadIds: (ids) => set({ resolvedThreadIds: ids }),
   overleafDocs: {},
   setOverleafDocs: (d) => set({ overleafDocs: d }),
   hoveredThreadId: null,
@@ -251,6 +255,7 @@ export const useAppStore = create<AppState>((set) => ({
     rootFolderId: '',
     syncDir: '',
     commentContexts: {},
+    resolvedThreadIds: new Set<string>(),
     overleafDocs: {},
     hoveredThreadId: null,
     focusedThreadId: null,