shutdown_simulator · Xcode MCP: Risk & Policy

WHAT IT DOES

What shutdown_simulator does on Xcode

AI agents invoke shutdown_simulator to trigger actions in Xcode. 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 shutdown_simulator needs a policy

This tool stops/terminates running simulator processes. It is an operational action (executing a shutdown command) rather than a simple read or data write. Misuse could disrupt active development/testing sessions by shutting down all simulators, but it is reversible (simulators can be rebooted), so it does not qualify as Destructive. Execute is the most appropriate category.

From the tool's definition Shutdown a simulator by UDID, or shutdown all running simulators

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

shutdown_simulator Rate-limited

shutdown_simulator 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": {
    "shutdown_simulator": {
      "limits": [
        {
          "counter": "shutdown_simulator_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 Xcode, so you can run agents against it safely.

FAQ

Questions about shutdown_simulator

What does the shutdown_simulator tool do? +

Shutdown a simulator by UDID, or shutdown all running simulators. It is categorised as a Execute tool in the Xcode MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on shutdown_simulator? +

Register the Xcode MCP server in PolicyLayer and add a rule for shutdown_simulator: 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 Xcode. Nothing to install.

What risk level is shutdown_simulator? +

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

Can I rate-limit shutdown_simulator? +

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

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

shutdown_simulator is provided by the Xcode MCP server (xcode-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

// THE FULL RECORD

shutdown_simulator is one line of Xcode's registry record.

The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.

Teams ship this data inside their own products. See what a licence covers →