diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 3eed026..cb98e1d 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -129,6 +129,10 @@ jobs:
           # Windows batch files MUST be CRLF — cmd.exe mis-parses LF-only files
           find "$stage_dir" -type f \( -name '*.bat' -o -name '*.cmd' -o -name '*.ps1' \) -print0 \
             | xargs -0 -I {} sh -c 'sed -i "s/\r$//; s/$/\r/" "{}"'
+          # Strip UTF-8 BOM from .bat files — cmd.exe interprets BOM as
+          # part of the first command and reports "not internal/external command"
+          find "$stage_dir" -type f \( -name '*.bat' -o -name '*.cmd' \) -print0 \
+            | xargs -0 -I {} sh -c 'sed -i "1s/^\xef\xbb\xbf//" "{}"'
           # Ensure shell scripts stay LF (mac/linux double-click won't run otherwise)
           find "$stage_dir" -type f \( -name '*.sh' -o -name '*.command' -o -name '*.mjs' -o -name '*.js' \) -print0 \
             | xargs -0 -I {} sh -c 'sed -i "s/\r$//" "{}"'
diff --git a/portable/config-server/server.js b/portable/config-server/server.js
index 15232e4..ad71940 100644
--- a/portable/config-server/server.js
+++ b/portable/config-server/server.js
@@ -419,6 +419,50 @@ const server = http.createServer((req, res) => {
     return;
   }
 
+  // API: Update status — read update-available.json written by check-update.mjs
+  // Returns { available: false } if no info or stale; otherwise the manifest payload.
+  if (req.url === '/api/update-status' && req.method === 'GET') {
+    try {
+      const stateDir = process.env.OPENCLAW_STATE_DIR
+        || path.join(__dirname, '../data/.openclaw');
+      const updateFile = path.join(stateDir, 'update-available.json');
+      if (!fs.existsSync(updateFile)) {
+        res.writeHead(200, { 'Content-Type': 'application/json' });
+        res.end(JSON.stringify({ available: false, reason: 'no-check-yet' }));
+        return;
+      }
+      const payload = JSON.parse(fs.readFileSync(updateFile, 'utf8'));
+      res.writeHead(200, { 'Content-Type': 'application/json' });
+      res.end(JSON.stringify(payload));
+    } catch (err) {
+      res.writeHead(200, { 'Content-Type': 'application/json' });
+      res.end(JSON.stringify({ available: false, reason: 'read-failed', error: err.message }));
+    }
+    return;
+  }
+
+  // API: Trigger update check on demand (so users can press a "Check now" button)
+  if (req.url === '/api/update-check' && req.method === 'POST') {
+    (async () => {
+      try {
+        const mod = await import('../lib/check-update.mjs');
+        const portableRoot = path.join(__dirname, '..');
+        const versionFilePath = fs.existsSync(path.join(portableRoot, 'OPENCLAW_VERSION'))
+          ? path.join(portableRoot, 'OPENCLAW_VERSION')
+          : path.join(portableRoot, '..', 'OPENCLAW_VERSION');
+        const stateDir = process.env.OPENCLAW_STATE_DIR
+          || path.join(portableRoot, 'data/.openclaw');
+        const result = await mod.checkUpdate({ versionFilePath, stateDir });
+        res.writeHead(200, { 'Content-Type': 'application/json' });
+        res.end(JSON.stringify(result));
+      } catch (err) {
+        res.writeHead(500, { 'Content-Type': 'application/json' });
+        res.end(JSON.stringify({ error: err.message }));
+      }
+    })();
+    return;
+  }
+
   // API: Re-run bootstrap to inject the uclaw-cloud provider
   if (req.url === '/api/xiapan/bind' && req.method === 'POST') {
     (async () => {
diff --git a/portable/lib/check-update.mjs b/portable/lib/check-update.mjs
new file mode 100644
index 0000000..ede2535
--- /dev/null
+++ b/portable/lib/check-update.mjs
@@ -0,0 +1,192 @@
+// 自动更新检查（轻量版）
+//
+// 流程：
+//   1. 读取 OPENCLAW_VERSION 文件得到当前版本号
+//   2. 5s timeout 拉 OSS 上的 latest.json
+//   3. 比对版本号，有新版就写 update-available.json 到 STATE_DIR
+//   4. Welcome.html / Config.html 启动时读这个文件，有就显示提示条
+//
+// 设计原则：
+//   - 静默失败：网络坏、OSS 挂、json 格式错、本地版本号缺失，都不能影响 OpenClaw 启动
+//   - 只读不下载：检查到新版只写 update-available.json，下载交给用户点链接到浏览器去做
+//   - 异步：调用方应该 detach 跑（Windows-Start.bat 用 start /B），不阻塞主流程
+//
+// latest.json 格式（你在 OSS 上手动维护或用 publish-latest.mjs 生成）：
+// {
+//   "version": "2026.4.30",
+//   "releaseDate": "2026-05-03",
+//   "downloadUrl": "https://u-claw-oss.56chat.cn/u-claw-open/u-claw-portable-v2026.4.30.zip",
+//   "releasePageUrl": "https://github.com/dongsheng123132/u-claw/releases/tag/v2026.4.30",
+//   "notes": "修复 xxx，新增 yyy"
+// }
+
+import { existsSync, readFileSync, writeFileSync, mkdirSync } from 'node:fs';
+import { dirname, resolve } from 'node:path';
+
+const DEFAULT_MANIFEST_URL = process.env.UCLAW_UPDATE_MANIFEST_URL
+  || 'https://u-claw-oss.56chat.cn/u-claw-open/latest.json';
+
+const DEFAULT_TIMEOUT_MS = 5000;
+
+function log(level, msg) {
+  const stream = level === 'error' ? process.stderr : process.stdout;
+  stream.write(`[check-update] ${msg}\n`);
+}
+
+function readVersionFile(versionFilePath) {
+  try {
+    if (!existsSync(versionFilePath)) return null;
+    const raw = readFileSync(versionFilePath, 'utf8').trim();
+    return raw || null;
+  } catch (err) {
+    log('error', `cannot read ${versionFilePath}: ${err.message}`);
+    return null;
+  }
+}
+
+// 简单语义比较：把 "2026.4.30" 拆成 [2026, 4, 30] 后逐位比
+// 不是 semver 但够用。返回 -1/0/1（remote 相对 local）
+function compareVersions(local, remote) {
+  if (!local || !remote) return 0;
+  const a = String(local).split('.').map((s) => parseInt(s, 10) || 0);
+  const b = String(remote).split('.').map((s) => parseInt(s, 10) || 0);
+  const len = Math.max(a.length, b.length);
+  for (let i = 0; i < len; i++) {
+    const ai = a[i] || 0;
+    const bi = b[i] || 0;
+    if (bi > ai) return 1;
+    if (bi < ai) return -1;
+  }
+  return 0;
+}
+
+async function fetchLatest(url, timeoutMs) {
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), timeoutMs);
+  try {
+    const res = await fetch(url, {
+      signal: controller.signal,
+      // 加随机参数避开 OSS / CDN 缓存
+      cache: 'no-store',
+      headers: { 'cache-control': 'no-cache' },
+    });
+    if (!res.ok) {
+      throw new Error(`HTTP ${res.status}`);
+    }
+    return await res.json();
+  } finally {
+    clearTimeout(timer);
+  }
+}
+
+function writeUpdateInfo(stateDir, payload) {
+  const filePath = resolve(stateDir, 'update-available.json');
+  try {
+    if (!existsSync(stateDir)) mkdirSync(stateDir, { recursive: true });
+    writeFileSync(filePath, JSON.stringify(payload, null, 2) + '\n', 'utf8');
+    return filePath;
+  } catch (err) {
+    log('error', `cannot write update-available.json: ${err.message}`);
+    return null;
+  }
+}
+
+function clearUpdateInfo(stateDir) {
+  const filePath = resolve(stateDir, 'update-available.json');
+  try {
+    if (existsSync(filePath)) {
+      writeFileSync(filePath, JSON.stringify({ available: false, checkedAt: new Date().toISOString() }, null, 2) + '\n', 'utf8');
+    }
+  } catch {
+    // 静默
+  }
+}
+
+export async function checkUpdate({
+  versionFilePath,
+  stateDir,
+  manifestUrl = DEFAULT_MANIFEST_URL,
+  timeoutMs = DEFAULT_TIMEOUT_MS,
+} = {}) {
+  if (!versionFilePath || !stateDir) {
+    return { ok: false, reason: 'missing-paths' };
+  }
+
+  const localVersion = readVersionFile(versionFilePath);
+  if (!localVersion) {
+    log('error', 'local OPENCLAW_VERSION not found, skip');
+    return { ok: false, reason: 'no-local-version' };
+  }
+
+  let remote;
+  try {
+    remote = await fetchLatest(manifestUrl, timeoutMs);
+  } catch (err) {
+    // 静默失败 — 网络坏不能影响用户用 U-Claw
+    log('error', `fetch ${manifestUrl} failed: ${err.message}`);
+    return { ok: false, reason: 'fetch-failed', error: err.message };
+  }
+
+  if (!remote || typeof remote !== 'object' || !remote.version) {
+    log('error', 'remote manifest invalid (missing version)');
+    return { ok: false, reason: 'invalid-manifest' };
+  }
+
+  const cmp = compareVersions(localVersion, remote.version);
+  if (cmp <= 0) {
+    // 已是最新或更新（开发版可能比线上还新）
+    clearUpdateInfo(stateDir);
+    log('info', `up to date (local=${localVersion}, remote=${remote.version})`);
+    return { ok: true, available: false, localVersion, remoteVersion: remote.version };
+  }
+
+  // 有新版
+  const payload = {
+    available: true,
+    checkedAt: new Date().toISOString(),
+    localVersion,
+    remoteVersion: remote.version,
+    releaseDate: remote.releaseDate || null,
+    downloadUrl: remote.downloadUrl || null,
+    releasePageUrl: remote.releasePageUrl || null,
+    notes: remote.notes || null,
+  };
+  const filePath = writeUpdateInfo(stateDir, payload);
+  log('info', `new version available: ${remote.version} (local=${localVersion})`);
+  return { ok: true, available: true, ...payload, filePath };
+}
+
+// CLI:
+//   node check-update.mjs <version-file> <state-dir> [manifest-url]
+//   env UCLAW_VERSION_FILE / UCLAW_STATE_DIR / UCLAW_UPDATE_MANIFEST_URL
+import { pathToFileURL } from 'node:url';
+const isMain = (() => {
+  try {
+    if (!process.argv[1]) return false;
+    return import.meta.url === pathToFileURL(process.argv[1]).href;
+  } catch {
+    return false;
+  }
+})();
+
+if (isMain) {
+  const versionFilePath = process.argv[2] || process.env.UCLAW_VERSION_FILE;
+  const stateDir = process.argv[3] || process.env.UCLAW_STATE_DIR;
+  const manifestUrl = process.argv[4] || process.env.UCLAW_UPDATE_MANIFEST_URL || DEFAULT_MANIFEST_URL;
+
+  if (!versionFilePath || !stateDir) {
+    process.stderr.write('Usage: node check-update.mjs <version-file> <state-dir> [manifest-url]\n');
+    process.exit(2);
+  }
+
+  checkUpdate({ versionFilePath, stateDir, manifestUrl })
+    .then((res) => {
+      process.stdout.write(`${JSON.stringify(res)}\n`);
+      // 退出码：0=正常（无论是否有新版），1=失败但已记录
+      process.exit(res.ok ? 0 : 1);
+    })
+    .catch((err) => {
+      process.stderr.write(`check-update fatal: ${err.message}\n`);
+      process.exit(1);
+    });
+}
diff --git a/portable/lib/publish-latest.mjs b/portable/lib/publish-latest.mjs
new file mode 100644
index 0000000..0fc6c34
--- /dev/null
+++ b/portable/lib/publish-latest.mjs
@@ -0,0 +1,112 @@
+// 发版辅助：生成 latest.json 用于上传到阿里云 OSS
+//
+// 用法（在仓库根目录跑）：
+//   node portable/lib/publish-latest.mjs
+//   node portable/lib/publish-latest.mjs --notes "修复了 xxx"
+//
+// 输出：
+//   - dist/latest.json — 你手动（或 ossutil）上传到 OSS 的同一个路径
+//
+// 上传命令示例（自己装 ossutil 后用）：
+//   ossutil cp dist/latest.json oss://u-claw-oss/u-claw-open/latest.json
+//
+// 这个脚本不直接调 OSS，避免硬编码 access key。把生成 + 上传分开，发版人自己负责上传。
+
+import { readFileSync, writeFileSync, existsSync, mkdirSync } from 'node:fs';
+import { resolve, dirname } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const REPO_ROOT = resolve(__dirname, '../..');
+
+// 默认 OSS 路径前缀（你可以改成自己的 bucket / domain）
+const DEFAULT_OSS_BASE = 'https://u-claw-oss.56chat.cn/u-claw-open';
+const GH_RELEASES_BASE = 'https://github.com/dongsheng123132/u-claw/releases';
+
+function parseArgs(argv) {
+  const args = { notes: '', ossBase: DEFAULT_OSS_BASE };
+  for (let i = 2; i < argv.length; i++) {
+    const a = argv[i];
+    if (a === '--notes' || a === '-n') args.notes = argv[++i] || '';
+    else if (a === '--oss-base') args.ossBase = argv[++i] || DEFAULT_OSS_BASE;
+    else if (a === '--help' || a === '-h') {
+      process.stdout.write([
+        'Usage: node portable/lib/publish-latest.mjs [options]',
+        '  --notes "<text>"      Release notes (single line)',
+        '  --oss-base <url>      OSS public URL prefix (default: ' + DEFAULT_OSS_BASE + ')',
+        '  --help                Show this help',
+        '',
+        'Output: dist/latest.json — upload it to <oss-base>/latest.json',
+      ].join('\n') + '\n');
+      process.exit(0);
+    }
+  }
+  return args;
+}
+
+function readVersion() {
+  const versionFile = resolve(REPO_ROOT, 'OPENCLAW_VERSION');
+  if (!existsSync(versionFile)) {
+    throw new Error(`OPENCLAW_VERSION file not found at ${versionFile}`);
+  }
+  const v = readFileSync(versionFile, 'utf8').trim();
+  if (!v) throw new Error('OPENCLAW_VERSION is empty');
+  return v;
+}
+
+function todayIso() {
+  const d = new Date();
+  const yyyy = d.getFullYear();
+  const mm = String(d.getMonth() + 1).padStart(2, '0');
+  const dd = String(d.getDate()).padStart(2, '0');
+  return `${yyyy}-${mm}-${dd}`;
+}
+
+function main() {
+  const args = parseArgs(process.argv);
+  const version = readVersion();
+  const tag = `v${version}`;
+
+  // Naming convention matches release.yml:
+  // dist/u-claw-portable-${tag_name}.zip
+  const zipName = `u-claw-portable-${tag}.zip`;
+  const downloadUrl = `${args.ossBase}/${zipName}`;
+  const releasePageUrl = `${GH_RELEASES_BASE}/tag/${tag}`;
+
+  const manifest = {
+    version,
+    releaseDate: todayIso(),
+    downloadUrl,
+    releasePageUrl,
+    notes: args.notes || '',
+    // Mirror fallback if user wants — check-update.mjs only looks at the top-level fields
+    mirrors: {
+      oss: downloadUrl,
+      github: `${releasePageUrl}/${zipName}`,
+    },
+  };
+
+  const distDir = resolve(REPO_ROOT, 'dist');
+  if (!existsSync(distDir)) mkdirSync(distDir, { recursive: true });
+  const outFile = resolve(distDir, 'latest.json');
+  writeFileSync(outFile, JSON.stringify(manifest, null, 2) + '\n', 'utf8');
+
+  process.stdout.write(`\nGenerated: ${outFile}\n`);
+  process.stdout.write(`Version:   ${version}\n`);
+  process.stdout.write(`Download:  ${downloadUrl}\n`);
+  process.stdout.write('\nNext steps (manual):\n');
+  process.stdout.write(`  1. Upload portable zip to OSS: ${args.ossBase}/${zipName}\n`);
+  process.stdout.write(`  2. Upload latest.json to OSS:  ${args.ossBase}/latest.json\n`);
+  process.stdout.write('\nExample (with ossutil):\n');
+  process.stdout.write(`  ossutil cp dist/${zipName} oss://<your-bucket>/u-claw-open/${zipName}\n`);
+  process.stdout.write(`  ossutil cp dist/latest.json oss://<your-bucket>/u-claw-open/latest.json\n`);
+  process.stdout.write('\nVerify after upload:\n');
+  process.stdout.write(`  curl -s ${args.ossBase}/latest.json | head -20\n\n`);
+}
+
+try {
+  main();
+} catch (err) {
+  process.stderr.write(`publish-latest error: ${err.message}\n`);
+  process.exit(1);
+}