ssh_shell_send · SSH MCP Server MCP: Risk & Policy

WHAT IT DOES

What ssh_shell_send does on SSH MCP Server

AI agents invoke ssh_shell_send to trigger actions in SSH MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why ssh_shell_send needs a policy

Sending input to an interactive shell session can execute arbitrary commands on the remote server, including destructive, financial, or other high-impact operations. Since the blast radius encompasses the full capability of whatever shell is running (potentially root), this is critical severity.

From the tool's definition 'Send input to an interactive shell session' — this tool sends arbitrary input to an active interactive shell, enabling execution of any command on a remote system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

ssh_shell_send Rate-limited

ssh_shell_send stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "ssh_shell_send": {
      "limits": [
        {
          "counter": "ssh_shell_send_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches SSH MCP Server, so you can run agents against it safely.

FAQ

Questions about ssh_shell_send

What does the ssh_shell_send tool do? +

Send input to an interactive shell session. It is categorised as a Execute tool in the SSH MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on ssh_shell_send? +

Register the SSH MCP Server MCP server in PolicyLayer and add a rule for ssh_shell_send: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches SSH MCP Server. Nothing to install.

What risk level is ssh_shell_send? +

ssh_shell_send is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit ssh_shell_send? +

Yes. Add a rate_limit block to the ssh_shell_send rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block ssh_shell_send completely? +

Set action: deny in the PolicyLayer policy for ssh_shell_send. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides ssh_shell_send? +

ssh_shell_send is provided by the SSH MCP Server MCP server (kpanuragh/ssh-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.