diff --git a/client/app.js b/client/app.js
deleted file mode 100644
index ea593ec..0000000
--- a/client/app.js
+++ /dev/null
@@ -1,362 +0,0 @@
-'use strict';
-
-const API = '';  // same origin
-
-// ── State ────────────────────────────────────────────────────────────────────
-
-let profiles = [];
-let sessions = [];          // [{id, profile_id, last_active, preview}]
-let currentSession = null;  // session id
-let ws = null;
-let streaming = false;
-let currentBubble = null;   // DOM element being streamed into
-
-// ── DOM refs ─────────────────────────────────────────────────────────────────
-
-const profileSelect  = document.getElementById('profile-select');
-const btnNew         = document.getElementById('btn-new');
-const sessionList    = document.getElementById('session-list');
-const chatHeader     = document.getElementById('chat-header');
-const messagesEl     = document.getElementById('messages');
-const textarea       = document.getElementById('input');
-const btnSend        = document.getElementById('btn-send');
-
-// ── Init ─────────────────────────────────────────────────────────────────────
-
-async function init() {
-  await loadProfiles();
-  await loadSessions();
-  textarea.addEventListener('keydown', onKey);
-  btnSend.addEventListener('click', sendMessage);
-  btnNew.addEventListener('click', createSession);
-  textarea.addEventListener('input', autoResize);
-}
-
-// ── Profiles ─────────────────────────────────────────────────────────────────
-
-async function loadProfiles() {
-  try {
-    const res = await fetch(`${API}/agents/profiles`);
-    profiles = await res.json();
-    profileSelect.innerHTML = profiles.map(p =>
-      `<option value="${p.id}">${p.name}</option>`
-    ).join('');
-  } catch (e) {
-    console.error('Failed to load profiles', e);
-  }
-}
-
-// ── Sessions ─────────────────────────────────────────────────────────────────
-
-async function loadSessions() {
-  try {
-    const res = await fetch(`${API}/sessions`);
-    const data = await res.json();
-    sessions = data.map(s => ({ ...s, preview: '' }));
-    renderSessionList();
-  } catch (e) {
-    console.error('Failed to load sessions', e);
-  }
-}
-
-async function createSession() {
-  const profileId = profileSelect.value;
-  if (!profileId) return;
-  btnNew.disabled = true;
-  try {
-    const res = await fetch(`${API}/sessions`, {
-      method: 'POST',
-      headers: { 'Content-Type': 'application/json' },
-      body: JSON.stringify({ profile_id: profileId }),
-    });
-    const session = await res.json();
-    sessions.unshift({ ...session, preview: 'New conversation' });
-    renderSessionList();
-    await switchSession(session.session_id);
-  } catch (e) {
-    console.error('Failed to create session', e);
-  } finally {
-    btnNew.disabled = false;
-  }
-}
-
-async function switchSession(sessionId) {
-  if (currentSession === sessionId) return;
-  disconnectWS();
-  currentSession = sessionId;
-  renderSessionList();
-  await loadHistory(sessionId);
-  connectWS(sessionId);
-  setInputEnabled(true);
-}
-
-async function loadHistory(sessionId) {
-  messagesEl.innerHTML = '';
-  try {
-    const res = await fetch(`${API}/sessions/${sessionId}`);
-    const data = await res.json();
-    updateChatHeader(data.profile_id);
-
-    const profile = profiles.find(p => p.id === data.profile_id);
-
-    for (const msg of data.messages) {
-      if (msg.role === 'system') continue;
-      if (msg.role === 'user') {
-        appendMessage('user', msg.content);
-      } else if (msg.role === 'assistant' && msg.content) {
-        appendMessage('assistant', msg.content);
-      }
-    }
-    scrollToBottom();
-  } catch (e) {
-    console.error('Failed to load history', e);
-  }
-}
-
-function renderSessionList() {
-  if (sessions.length === 0) {
-    sessionList.innerHTML = '<div class="empty-sessions">No conversations yet</div>';
-    return;
-  }
-  sessionList.innerHTML = sessions.map(s => {
-    const profile = profiles.find(p => p.id === s.profile_id);
-    const name = profile ? profile.name : s.profile_id;
-    const time = formatTime(s.last_active);
-    const preview = s.preview || 'No messages yet';
-    const active = s.session_id === currentSession ? ' active' : '';
-    return `
-      <div class="session-item${active}" data-id="${s.session_id}">
-        <div class="s-body">
-          <div class="s-profile">${escHtml(name)}</div>
-          <div class="s-preview">${escHtml(preview)}</div>
-          <div class="s-time">${time}</div>
-        </div>
-        <button class="btn-delete" data-id="${s.session_id}" title="Delete">×</button>
-      </div>`;
-  }).join('');
-
-  sessionList.querySelectorAll('.session-item').forEach(el => {
-    el.addEventListener('click', () => switchSession(el.dataset.id));
-  });
-  sessionList.querySelectorAll('.btn-delete').forEach(btn => {
-    btn.addEventListener('click', (e) => {
-      e.stopPropagation();
-      deleteSession(btn.dataset.id);
-    });
-  });
-}
-
-async function deleteSession(sessionId) {
-  try {
-    await fetch(`${API}/sessions/${sessionId}`, { method: 'DELETE' });
-  } catch (e) {
-    console.error('Failed to delete session', e);
-  }
-  sessions = sessions.filter(s => s.session_id !== sessionId);
-
-  if (currentSession === sessionId) {
-    disconnectWS();
-    currentSession = null;
-    messagesEl.innerHTML = '<div class="empty-chat"><div class="icon">💬</div><p>Start a new conversation</p></div>';
-    chatHeader.textContent = 'Select a profile and start a new chat';
-    setInputEnabled(false);
-  }
-  renderSessionList();
-}
-
-function updateSessionPreview(sessionId, text) {
-  const s = sessions.find(s => s.session_id === sessionId);
-  if (s) s.preview = text.slice(0, 60);
-  renderSessionList();
-}
-
-// ── WebSocket ─────────────────────────────────────────────────────────────────
-
-function connectWS(sessionId) {
-  const proto = location.protocol === 'https:' ? 'wss' : 'ws';
-  const url = `${proto}://${location.host}/ws/sessions/${sessionId}`;
-  ws = new WebSocket(url);
-
-  ws.onopen = () => console.log('WS connected', sessionId);
-  ws.onclose = (e) => {
-    console.log('WS closed', e.code);
-    if (streaming) finishStream();
-  };
-  ws.onerror = (e) => console.error('WS error', e);
-  ws.onmessage = (e) => handleWsEvent(JSON.parse(e.data));
-}
-
-function disconnectWS() {
-  if (ws) { ws.close(); ws = null; }
-}
-
-function handleWsEvent(event) {
-  switch (event.type) {
-    case 'stream_start':
-      streaming = true;
-      removeTypingIndicator();
-      currentBubble = appendMessage('assistant', '');
-      currentBubble.classList.add('cursor');
-      break;
-
-    case 'stream_delta':
-      if (currentBubble) {
-        currentBubble.textContent += event.delta;
-        scrollToBottom();
-      }
-      break;
-
-    case 'tool_call':
-      appendToolCall(event);
-      scrollToBottom();
-      break;
-
-    case 'stream_end':
-      finishStream(event.content);
-      setInputEnabled(true);
-      break;
-
-    case 'error':
-      finishStream();
-      appendError(event.message);
-      setInputEnabled(true);
-      break;
-  }
-}
-
-function finishStream(finalContent) {
-  streaming = false;
-  removeTypingIndicator();
-  if (currentBubble) {
-    currentBubble.classList.remove('cursor');
-    if (finalContent !== undefined) {
-      currentBubble.textContent = finalContent;
-      updateSessionPreview(currentSession, finalContent);
-    }
-    currentBubble = null;
-  }
-  scrollToBottom();
-}
-
-// ── Sending ───────────────────────────────────────────────────────────────────
-
-async function sendMessage() {
-  const text = textarea.value.trim();
-  if (!text || !ws || ws.readyState !== WebSocket.OPEN || streaming) return;
-
-  textarea.value = '';
-  autoResize();
-  setInputEnabled(false);
-
-  appendMessage('user', text);
-  appendTypingIndicator();
-  scrollToBottom();
-
-  ws.send(JSON.stringify({ type: 'message', content: text }));
-}
-
-function onKey(e) {
-  if (e.key === 'Enter' && !e.shiftKey) {
-    e.preventDefault();
-    sendMessage();
-  }
-}
-
-// ── DOM helpers ───────────────────────────────────────────────────────────────
-
-function appendMessage(role, content) {
-  const msg = document.createElement('div');
-  msg.className = `msg ${role}`;
-
-  const bubble = document.createElement('div');
-  bubble.className = 'bubble';
-  bubble.textContent = content;
-
-  const time = document.createElement('div');
-  time.className = 'msg-time';
-  time.textContent = formatTime(new Date().toISOString());
-
-  msg.appendChild(bubble);
-  msg.appendChild(time);
-  messagesEl.appendChild(msg);
-  return bubble;
-}
-
-function appendToolCall(event) {
-  const icons = { web_search: '🔍', filesystem: '📁', http_request: '🌐', code_exec: '⚙️', terminal: '💻' };
-  const icon = icons[event.tool] || '🔧';
-  const card = document.createElement('div');
-  card.className = `tool-card${event.success ? '' : ' error'}`;
-  card.innerHTML = `
-    <div class="tool-header">
-      <span class="tool-icon">${icon}</span>
-      <span>${escHtml(event.tool)}</span>
-    </div>
-    <div class="tool-result">${escHtml(event.result)}</div>`;
-  messagesEl.appendChild(card);
-}
-
-function appendTypingIndicator() {
-  removeTypingIndicator();
-  const el = document.createElement('div');
-  el.className = 'typing';
-  el.id = 'typing';
-  el.innerHTML = '<span></span><span></span><span></span>';
-  messagesEl.appendChild(el);
-}
-
-function removeTypingIndicator() {
-  document.getElementById('typing')?.remove();
-}
-
-function appendError(message) {
-  const el = document.createElement('div');
-  el.className = 'msg-error';
-  el.textContent = `Error: ${message}`;
-  messagesEl.appendChild(el);
-}
-
-function updateChatHeader(profileId) {
-  const profile = profiles.find(p => p.id === profileId);
-  const name = profile ? profile.name : profileId;
-  chatHeader.innerHTML = `<span class="profile-badge">${escHtml(profileId)}</span> ${escHtml(name)}`;
-}
-
-function setInputEnabled(enabled) {
-  textarea.disabled = !enabled;
-  btnSend.disabled = !enabled;
-  if (enabled) textarea.focus();
-}
-
-function scrollToBottom() {
-  messagesEl.scrollTop = messagesEl.scrollHeight;
-}
-
-function autoResize() {
-  textarea.style.height = 'auto';
-  textarea.style.height = Math.min(textarea.scrollHeight, 180) + 'px';
-}
-
-function escHtml(str) {
-  return String(str)
-    .replace(/&/g, '&amp;')
-    .replace(/</g, '&lt;')
-    .replace(/>/g, '&gt;')
-    .replace(/"/g, '&quot;');
-}
-
-function formatTime(iso) {
-  if (!iso) return '';
-  const d = new Date(iso);
-  if (isNaN(d)) return '';
-  const now = new Date();
-  const diff = now - d;
-  if (diff < 60_000) return 'just now';
-  if (diff < 3_600_000) return `${Math.floor(diff / 60_000)}m ago`;
-  if (diff < 86_400_000) return d.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
-  return d.toLocaleDateString();
-}
-
-// ── Start ─────────────────────────────────────────────────────────────────────
-
-init();
diff --git a/client/js/app.js b/client/js/app.js
index 445f63c..3522ee2 100644
--- a/client/js/app.js
+++ b/client/js/app.js
@@ -34,6 +34,7 @@
 let sessions         = [];
 let currentId        = null;
 let streaming        = false;
+let inputAllowed     = false;  // true when a session is open and ready for input
 let currentBubble    = null;
 let currentThinking  = null;
 let pendingImages    = [];   // {dataUrl} — images to send as base64
@@ -193,6 +194,7 @@
 
 async function deleteSession(sessionId) {
   await api.deleteSession(sessionId).catch(console.error);
+  localStorage.removeItem('navi_draft_' + sessionId);
   sessions = sessions.filter(s => s.session_id !== sessionId);
   if (currentId === sessionId) {
     abandonStream();
@@ -229,8 +231,7 @@
       streaming = true;
       currentBubble = null;
       currentThinking = null;
-      // Switch send button to stop mode; disable attach.
-      setStreamMode(true);
+      updateInputUI();
       appendTypingIndicator(messagesEl);
       scrollToBottom(messagesEl);
       break;
@@ -298,13 +299,11 @@
     case 'stream_end':
       finishStream(event.content);
       updateTokenCounter(event.context_tokens, event.max_context_tokens);
-      setStreamMode(false);
       setInputEnabled(true);
       break;
 
     case 'stream_stopped':
       finishStream();
-      setStreamMode(false);
       setInputEnabled(true);
       break;
 
@@ -328,7 +327,6 @@
 
     case 'error':
       finishStream();
-      setStreamMode(false);
       appendError(messagesEl, event.message);
       setInputEnabled(true);
       break;
@@ -362,7 +360,6 @@
   currentThinking = null;
   pendingToolCard = null;
   pendingSubStep  = null;
-  setStreamMode(false);
   // Don't clear pendingImages/pendingFiles — those belong to the user's draft
 }
 
@@ -443,44 +440,36 @@
 }
 
 /**
- * Only disables the send button — textarea stays enabled so the user can
- * keep typing while the model is responding.
+ * Single source of truth for input bar state.
+ * Derives button appearance from: streaming, inputAllowed, uploadCount.
  */
-function setInputEnabled(on) {
-  btnSend.disabled   = !on || uploadCount > 0;
-  btnAttach.disabled = !on;
-  if (on) textarea.focus();
-}
-
-/** Switch the send button between send (↑) and stop (■) modes. */
-function setStreamMode(active) {
-  if (active) {
+function updateInputUI() {
+  if (streaming) {
+    btnSend.disabled    = false;
     btnSend.textContent = '■';
     btnSend.title       = 'Stop generation';
-    btnSend.disabled    = false;
     btnSend.classList.add('stop-mode');
     btnAttach.disabled  = true;
   } else {
+    btnSend.disabled    = !inputAllowed || uploadCount > 0;
     btnSend.textContent = '↑';
     btnSend.title       = 'Send (Enter)';
     btnSend.classList.remove('stop-mode');
+    btnAttach.disabled  = !inputAllowed;
+    if (inputAllowed) textarea.focus();
   }
 }
 
+function setInputEnabled(on) {
+  inputAllowed = on;
+  updateInputUI();
+}
+
 function stopGeneration() {
   ws.stop();
   btnSend.disabled = true;  // prevent double-click while waiting for stream_stopped
 }
 
-/** Re-evaluate send button state based on current upload activity (called from upload callbacks). */
-function syncSendButton() {
-  // Only touch send — don't change btnAttach (that's controlled by streaming state).
-  // If streaming, send stays disabled regardless of upload state.
-  if (!streaming) {
-    btnSend.disabled = uploadCount > 0;
-  }
-}
-
 function onTextareaInput() {
   autoResize();
   saveDraft();
@@ -505,7 +494,7 @@
 function addArbitraryFile(file) {
   if (!currentId) return;
   uploadCount++;
-  syncSendButton();
+  updateInputUI();
 
   // Show upload progress
   uploadProgressBar.hidden = false;
@@ -527,7 +516,7 @@
   xhr.onload = () => {
     uploadCount--;
     if (uploadCount === 0) uploadProgressBar.hidden = true;
-    syncSendButton();
+    updateInputUI();
 
     if (xhr.status === 201) {
       const info = JSON.parse(xhr.responseText);
@@ -543,7 +532,7 @@
   xhr.onerror = () => {
     uploadCount--;
     if (uploadCount === 0) uploadProgressBar.hidden = true;
-    syncSendButton();
+    updateInputUI();
     alert(`Upload failed: network error`);
   };
 
@@ -630,7 +619,7 @@
     btn.addEventListener('click', () => {
       pendingFiles.splice(pendingFiles.indexOf(info), 1);
       renderPreviewStrip();
-      syncSendButton();
+      updateInputUI();
     });
 
     badge.append(icon, infoEl, btn);