diff --git a/src/gateway/server-v2.ts b/src/gateway/server-v2.ts
index 3bbf154..f385d9f 100644
--- a/src/gateway/server-v2.ts
+++ b/src/gateway/server-v2.ts
@@ -12937,6 +12937,44 @@ app.get('/api/ollama/models', async (_req, res) => {
   }
 });
 
+// GET /api/model-context?model=<name>  — return context window size for a model
+app.get('/api/model-context', requireAuth, async (req, res) => {
+  const model = String(req.query.model || '').trim();
+  // Claude models always have 200K context
+  if (!model || model.toLowerCase().includes('claude')) {
+    res.json({ contextWindow: 200000 });
+    return;
+  }
+  // For Ollama models, query /api/show
+  try {
+    const ollamaEndpoint = (getConfig().getConfig() as any).ollama?.endpoint || 'http://localhost:11434';
+    const response = await fetch(`${ollamaEndpoint}/api/show`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ name: model }),
+    });
+    if (!response.ok) { res.json({ contextWindow: null }); return; }
+    const data = await response.json() as any;
+    // Prefer model_info context length (most accurate)
+    let ctxWindow: number | null = null;
+    const modelInfo = data.model_info || {};
+    for (const key of Object.keys(modelInfo)) {
+      if (key.endsWith('.context_length') && typeof modelInfo[key] === 'number') {
+        ctxWindow = modelInfo[key];
+        break;
+      }
+    }
+    // Fallback: parse num_ctx from parameters string
+    if (!ctxWindow && typeof data.parameters === 'string') {
+      const m = data.parameters.match(/\bnum_ctx\s+(\d+)/);
+      if (m) ctxWindow = parseInt(m[1], 10);
+    }
+    res.json({ contextWindow: ctxWindow });
+  } catch (err: any) {
+    res.json({ contextWindow: null, error: err.message });
+  }
+});
+
 
 import * as osModule from 'os';
 
diff --git a/web-ui/code.js b/web-ui/code.js
index 2134470..69d42f7 100644
--- a/web-ui/code.js
+++ b/web-ui/code.js
@@ -3893,14 +3893,25 @@ function setCodeSbTab(tab) {
 }
 
 
-function _codeAiCtxMax() {
-  const m = (codeAiModel || '').toLowerCase();
-  if (!m || m.includes('claude')) return 200000;
-  // Common Ollama context windows
-  if (m.includes('llama3') || m.includes('llama-3') || m.includes('qwen')) return 128000;
-  if (m.includes('mistral') || m.includes('mixtral')) return 32000;
-  if (m.includes('gemma')) return 8192;
-  return 32000; // safe default for unknown local models
+let _codeAiCtxMaxCached = 200000; // default until server responds
+let _codeAiCtxMaxFetchedFor = ''; // model name the cache is valid for
+
+function _codeAiCtxMax() { return _codeAiCtxMaxCached; }
+
+async function _fetchModelCtxMax(model) {
+  const key = model || '';
+  if (key === _codeAiCtxMaxFetchedFor) return; // already fetched for this model
+  _codeAiCtxMaxFetchedFor = key;
+  try {
+    const url = '/api/model-context' + (key ? `?model=${encodeURIComponent(key)}` : '');
+    const r = await fetch(url, { headers: authHeaders() });
+    if (!r.ok) return;
+    const d = await r.json();
+    if (d.contextWindow) {
+      _codeAiCtxMaxCached = d.contextWindow;
+      updateSessionPanel();
+    }
+  } catch (_) {}
 }
 
 function updateSessionPanel() {
@@ -4143,6 +4154,8 @@ function csbModelChanged() {
   codeAiModel = sel ? sel.value : '';
   localStorage.setItem('codeAiModel', codeAiModel);
   updateCodeAiLabel();
+  _codeAiCtxMaxFetchedFor = ''; // invalidate cache so next fetch runs
+  _fetchModelCtxMax(codeAiModel);
 }
 
 function csbFontSize(val) {
@@ -4460,6 +4473,7 @@ function setupCodeVResize() {
     try { const inp = document.getElementById('csb-termpath'); if (inp && localTermPath) inp.value = localTermPath; } catch (e) {}
     try { await restoreLocalDirHandle(); } catch (e) {}
     try { updateSessionPanel(); } catch (e) {}
+    try { _fetchModelCtxMax(codeAiModel); } catch (e) {}
     try { codeSbRefresh(); } catch (e) {}
     try { companionConnect(); } catch (e) {}
     // 히스토리 없으면 세션 목록 표시