send_keys · Post-Exploitation tmux MCP Server MCP

WHAT IT DOES

What send_keys does on Post-Exploitation tmux MCP Server

AI agents invoke send_keys to trigger actions in Post-Exploitation tmux 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 send_keys needs a policy

Sending keystrokes to a tmux pane with Enter pressed is functionally equivalent to executing arbitrary commands in a terminal. The server is explicitly described as a 'Post-Exploitation' tool, amplifying the blast radius. While guardrails exist, they only apply when press_enter=True, and even with them, the tool can still run a wide range of commands.

From the tool's definition 'Send keystrokes to a tmux pane' with 'press_enter=True' — sending keys with Enter executes commands in a live terminal pane; guardrail-checked but still triggers execution of arbitrary input in a shell context

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

send_keys Rate-limited

send_keys 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": {
    "send_keys": {
      "limits": [
        {
          "counter": "send_keys_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 Post-Exploitation tmux MCP Server, so you can run agents against it safely.

FAQ

Questions about send_keys

What does the send_keys tool do? +

Send keystrokes to a tmux pane (guardrail-checked if press_enter=True). It is categorised as a Execute tool in the Post-Exploitation tmux 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 send_keys? +

Register the Post-Exploitation tmux MCP Server MCP server in PolicyLayer and add a rule for send_keys: 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 Post-Exploitation tmux MCP Server. Nothing to install.

What risk level is send_keys? +

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

Can I rate-limit send_keys? +

Yes. Add a rate_limit block to the send_keys 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 send_keys completely? +

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

send_keys is provided by the Post-Exploitation tmux MCP Server MCP server (raghavansv/tmux-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.