xcode_boot_simulator · Xcode MCP: Risk & Policy

WHAT IT DOES

What xcode_boot_simulator does on Xcode

AI agents invoke xcode_boot_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 xcode_boot_simulator needs a policy

Booting a simulator triggers an external operation (launching a simulator process) that changes system state. It is not a simple read, nor does it delete data or involve finances. The blast radius is medium — misuse could consume system resources or interfere with existing simulator sessions, but it is generally reversible by shutting the simulator down.

From the tool's definition Boot a simulator by UDID

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

xcode_boot_simulator Rate-limited

xcode_boot_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": {
    "xcode_boot_simulator": {
      "limits": [
        {
          "counter": "xcode_boot_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 xcode_boot_simulator

What does the xcode_boot_simulator tool do? +

Boot a simulator by UDID. 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 xcode_boot_simulator? +

Register the Xcode MCP server in PolicyLayer and add a rule for xcode_boot_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 xcode_boot_simulator? +

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

Can I rate-limit xcode_boot_simulator? +

Yes. Add a rate_limit block to the xcode_boot_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 xcode_boot_simulator completely? +

Set action: deny in the PolicyLayer policy for xcode_boot_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 xcode_boot_simulator? +

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