diff --git a/static/js/cookbookServe.js b/static/js/cookbookServe.js
index 189c4ae..6e71791 100644
--- a/static/js/cookbookServe.js
+++ b/static/js/cookbookServe.js
@@ -93,6 +93,67 @@ function _allGpuIds(count) {
   return Array.from({ length: Math.floor(n) }, (_, i) => String(i)).join(',');
 }
 
+function _selectedServeTarget(panel) {
+  const select = document.getElementById('hwfit-server-select') || document.getElementById('hwfit-dl-server');
+  const servers = Array.isArray(_envState.servers) ? _envState.servers : [];
+  let host = _envState.remoteHost || '';
+  let server = host ? servers.find(s => s.host === host) : null;
+  if (select && select.value != null) {
+    if (select.value === 'local') {
+      host = '';
+      server = servers.find(s => !s.host || s.host === 'local') || null;
+    } else {
+      const idx = /^\d+$/.test(String(select.value)) ? parseInt(select.value, 10) : -1;
+      server = servers.find(s => s.host === select.value) || (idx >= 0 ? servers[idx] : null) || null;
+      host = server?.host || '';
+    }
+  }
+  const venv = panel?.querySelector('[data-field="venv"]')?.value?.trim() || server?.envPath || _envState.envPath || '';
+  const label = host
+    ? (server?.name ? `${server.name} (${host})` : host)
+    : (server?.name || 'local server');
+  return {
+    host,
+    port: host ? (_getPort(host) || server?.port || '') : '',
+    venv,
+    label,
+  };
+}
+
+async function _fetchServeRuntimePackage(panel, backend) {
+  const packageByBackend = {
+    vllm: 'vllm',
+    sglang: 'sglang',
+    llamacpp: 'llama_cpp',
+    diffusers: 'diffusers',
+  };
+  const packageName = packageByBackend[backend];
+  if (!packageName) return null;
+  const target = _selectedServeTarget(panel);
+  const params = new URLSearchParams();
+  if (target.host) {
+    params.set('host', target.host);
+    if (target.port) params.set('ssh_port', target.port);
+    if (target.venv) params.set('venv', target.venv);
+  }
+  const res = await fetch('/api/cookbook/packages' + (params.toString() ? '?' + params.toString() : ''), { credentials: 'same-origin' });
+  if (!res.ok) throw new Error(`HTTP ${res.status}`);
+  const data = await res.json();
+  const pkg = (data.packages || []).find(p => p.name === packageName);
+  return { pkg, target };
+}
+
+function _runtimeNoteText(backend, pkg, target) {
+  const labels = { vllm: 'vLLM', sglang: 'SGLang', llamacpp: 'llama.cpp', diffusers: 'Diffusers' };
+  const label = labels[backend] || backend;
+  if (!pkg) return `${label} readiness unavailable for ${target.label}.`;
+  const note = pkg.status_note || pkg.update_note || '';
+  if (pkg.installed) {
+    return note ? `${label} ready on ${target.label}: ${note}` : `${label} ready on ${target.label}.`;
+  }
+  return note ? `${label} missing on ${target.label}: ${note}` : `${label} missing on ${target.label}.`;
+}
+
 // ── Filter/sort cached model list ──
 
 function _filterCachedList() {
@@ -399,7 +460,9 @@ function _rerenderCachedModels() {
 
       // Toggle — close if already open
       if (item.classList.contains('doclib-card-expanded')) {
-        item.querySelector('.hwfit-serve-panel')?.remove();
+        const existingPanel = item.querySelector('.hwfit-serve-panel');
+        existingPanel?._cleanupRuntimeReadiness?.();
+        existingPanel?.remove();
         item.classList.remove('doclib-card-expanded');
         item.style.flexDirection = '';
         item.style.alignItems = '';
@@ -410,7 +473,9 @@ function _rerenderCachedModels() {
 
       // Collapse any other expanded
       list.querySelectorAll('.doclib-card-expanded').forEach(c => {
-        c.querySelector('.hwfit-serve-panel')?.remove();
+        const openPanel = c.querySelector('.hwfit-serve-panel');
+        openPanel?._cleanupRuntimeReadiness?.();
+        openPanel?.remove();
         c.classList.remove('doclib-card-expanded');
         c.style.flexDirection = '';
         c.style.alignItems = '';
@@ -509,6 +574,7 @@ function _rerenderCachedModels() {
       }
       panelHtml += `<label>${_l('GPUs','Toggle which GPUs to use')}<div class="cookbook-gpu-group">${_gpuBtnsHtml}</div><input type="hidden" class="hwfit-sf" data-field="gpus" value="${esc(defaultGpus)}" /></label>`;
       panelHtml += `</div>`;
+      panelHtml += `<div class="hwfit-serve-runtime-note" style="display:none;font-size:11px;line-height:1.35;color:var(--fg-muted);margin-top:-4px;"></div>`;
       if (_ggufChoices.length > 1) {
         panelHtml += `<div class="hwfit-serve-row hwfit-backend-llamacpp">`;
         panelHtml += `<label class="hwfit-backend-llamacpp">${_l('GGUF File','Choose the exact GGUF artifact to serve from this cached model folder.')}<select class="hwfit-sf hwfit-sf-wide" data-field="gguf_file">${_ggufOptions}</select></label>`;
@@ -856,6 +922,38 @@ function _rerenderCachedModels() {
       }
       updateBackendVisibility();
 
+      async function updateRuntimeReadinessNote() {
+        const note = panel.querySelector('.hwfit-serve-runtime-note');
+        if (!note) return;
+        const backend = panel.querySelector('[data-field="backend"]')?.value || 'vllm';
+        if (!['vllm', 'sglang', 'llamacpp', 'diffusers'].includes(backend)) {
+          note.style.display = 'none';
+          note.textContent = '';
+          return;
+        }
+        const seq = (panel._runtimeReadinessSeq || 0) + 1;
+        panel._runtimeReadinessSeq = seq;
+        note.style.display = '';
+        note.textContent = 'Checking runtime on selected server...';
+        try {
+          const { pkg, target } = await _fetchServeRuntimePackage(panel, backend);
+          if (panel._runtimeReadinessSeq !== seq) return;
+          note.textContent = _runtimeNoteText(backend, pkg, target);
+          note.style.color = pkg?.installed ? 'var(--fg-muted)' : 'var(--red)';
+        } catch (err) {
+          if (panel._runtimeReadinessSeq !== seq) return;
+          note.textContent = `Runtime readiness unavailable: ${err?.message || err}`;
+          note.style.color = 'var(--fg-muted)';
+        }
+      }
+      updateRuntimeReadinessNote();
+      const runtimeServerSelect = document.getElementById('hwfit-server-select') || document.getElementById('hwfit-dl-server');
+      if (runtimeServerSelect) {
+        const refreshRuntimeOnServerChange = () => updateRuntimeReadinessNote();
+        runtimeServerSelect.addEventListener('change', refreshRuntimeOnServerChange);
+        panel._cleanupRuntimeReadiness = () => runtimeServerSelect.removeEventListener('change', refreshRuntimeOnServerChange);
+      }
+
       // Wire save slots
       function _loadSlotIntoPanel(slotIdx) {
         const presets = _loadPresets();
@@ -939,6 +1037,7 @@ function _rerenderCachedModels() {
         const _gf = panel.querySelector('[data-field="gpus"]');
         if (_gf) _gf.value = activeGpus.join(',');
         updateBackendVisibility();
+        updateRuntimeReadinessNote();
         updateCmd();
         panel.querySelectorAll('.cookbook-slot-btn').forEach(b => b.classList.remove('active'));
         panel.querySelector(`.cookbook-slot-btn[data-slot="${slotIdx}"]`)?.classList.add('active');
@@ -1478,6 +1577,10 @@ function _rerenderCachedModels() {
             const extraEl = panel.querySelector('[data-field="extra"]');
             if (extraEl) extraEl.value = '';
             updateBackendVisibility();
+            updateRuntimeReadinessNote();
+          }
+          if (e.target.dataset.field === 'venv') {
+            updateRuntimeReadinessNote();
           }
           updateCmd();
         });
@@ -1509,6 +1612,7 @@ function _rerenderCachedModels() {
       // "back out" affordance next to Launch.
       panel.querySelector('.hwfit-serve-cancel')?.addEventListener('click', (ev) => {
         ev.stopPropagation();
+        panel._cleanupRuntimeReadiness?.();
         panel.remove();
         item.classList.remove('doclib-card-expanded');
         item.style.flexDirection = '';