ssh_signal · Mcp Ssh Live MCP: Risk & Policy

WHAT IT DOES

What ssh_signal does on Mcp Ssh Live

AI agents invoke ssh_signal to trigger actions in Mcp Ssh Live. 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_signal needs a policy

The tool name 'ssh_signal' strongly implies sending signals (e.g., SIGKILL, SIGTERM, SIGHUP) to remote processes over SSH. The server description explicitly mentions 'signal handling' as a capability. Sending signals to remote processes is an Execute-category action — it triggers external operations on a remote system and can terminate or alter running processes.

From the tool's definition Tool name 'ssh_signal' on a server described as enabling 'spawning long-running remote commands with live line-by-line output, signal handling, stdin input'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

ssh_signal Rate-limited

ssh_signal 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_signal": {
      "limits": [
        {
          "counter": "ssh_signal_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 Mcp Ssh Live, so you can run agents against it safely.

FAQ

Questions about ssh_signal

What does the ssh_signal tool do? +

ssh_signal. It is categorised as a Execute tool in the Mcp Ssh Live 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_signal? +

Register the Mcp Ssh Live MCP server in PolicyLayer and add a rule for ssh_signal: 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 Mcp Ssh Live. Nothing to install.

What risk level is ssh_signal? +

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

Can I rate-limit ssh_signal? +

Yes. Add a rate_limit block to the ssh_signal 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_signal completely? +

Set action: deny in the PolicyLayer policy for ssh_signal. 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_signal? +

ssh_signal is provided by the Mcp Ssh Live MCP server (pmboxbiz/mcp-ssh-live). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.