stop_auto_cycle · Tmux MCP Server MCP: Risk & Policy

WHAT IT DOES

What stop_auto_cycle does on Tmux MCP Server

AI agents invoke stop_auto_cycle 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_auto_cycle needs a policy

This tool triggers termination of an automated process running in a tmux session. While not destructive (the session itself persists), it actively halts an external operation with real-time effects, making it Execute rather than Write. The blast radius is high because stopping the wrong session's auto-cycle could disrupt critical background workflows, monitoring, or CI/CD processes.

From the tool's definition Tool stops an active auto-cycle for a tmux session. The parent server description indicates auto-cycles perform 'exit/continue cycles' and 'automated workflow features' that actively control tmux processes.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_auto_cycle Rate-limited

stop_auto_cycle 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_auto_cycle": {
      "limits": [
        {
          "counter": "stop_auto_cycle_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_auto_cycle

What does the stop_auto_cycle tool do? +

Stop an active auto-cycle 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_auto_cycle? +

Register the Tmux MCP Server MCP server in PolicyLayer and add a rule for stop_auto_cycle: 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_auto_cycle? +

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

Can I rate-limit stop_auto_cycle? +

Yes. Add a rate_limit block to the stop_auto_cycle 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_auto_cycle completely? +

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

stop_auto_cycle 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.