stop_message_timer · Tmux MCP Server MCP: Risk & Policy

WHAT IT DOES

What stop_message_timer does on Tmux MCP Server

AI agents invoke stop_message_timer to trigger actions in 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 stop_message_timer needs a policy

This tool controls active processes and timers within tmux sessions. While stopping a timer is less risky than starting one or sending arbitrary commands, it still executes an operation that affects the runtime behavior of external systems.

From the tool's definition Tool 'stop_message_timer' stops an active message timer in a tmux session. The ability to manipulate timers and affect tmux session behavior constitutes an Execute operation—it triggers a state change in an external process (the tmux session's timer…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_message_timer Rate-limited

stop_message_timer 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": {
    "stop_message_timer": {
      "limits": [
        {
          "counter": "stop_message_timer_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 Tmux MCP Server, so you can run agents against it safely.

FAQ

Questions about stop_message_timer

What does the stop_message_timer tool do? +

Stop an active message timer for a tmux session. It is categorised as a Execute tool in the 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 stop_message_timer? +

Register the Tmux MCP Server MCP server in PolicyLayer and add a rule for stop_message_timer: 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 Tmux MCP Server. Nothing to install.

What risk level is stop_message_timer? +

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

Can I rate-limit stop_message_timer? +

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

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

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