diff --git a/backend/agent_tools.py b/backend/agent_tools.py
index dc0b9c0..535b774 100644
--- a/backend/agent_tools.py
+++ b/backend/agent_tools.py
@@ -209,7 +209,8 @@ SHELL_READ_ONLY_COMMANDS: dict[str, set[str] | None] = {
     "nc": None, "nmap": None, "telnet": None, "tcpdump": None, "ethtool": None,
     "lspci": None, "lsusb": None, "dmidecode": None, "sysctl": None, "udevadm": None,
     "echo": None, "printf": None, "cd": None, "pwd": None, "export": None,
-    "test": None, "[": None,
+    "test": None, "[": None, "sleep": None,
+    "timeout": None, "nohup": None,
 }
 
 # etcdctl 由 classify_shell_command 中的专用块处理 (两段式命令)