boot_sim · Sl Test MCP: Risk & Policy

WHAT IT DOES

What boot_sim does on Sl Test

AI agents invoke boot_sim to trigger actions in Sl Test. 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 boot_sim needs a policy

Booting a simulator is an external operation that starts a system process. It is not a simple read, nor does it delete data or involve finances. It falls squarely in Execute as it triggers an external runtime environment. Misuse could consume system resources or interfere with other running simulators, warranting medium severity.

From the tool's definition 'Boots an iOS simulator' — starts/launches a simulator process, triggering an external system operation

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

boot_sim Rate-limited

boot_sim 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": {
    "boot_sim": {
      "limits": [
        {
          "counter": "boot_sim_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 Sl Test, so you can run agents against it safely.

FAQ

Questions about boot_sim

What does the boot_sim tool do? +

Boots an iOS simulator. IMPORTANT: You MUST provide the simulatorUuid parameter. Example: boot_sim({ simulatorUuid:. It is categorised as a Execute tool in the Sl Test MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on boot_sim? +

Register the Sl Test MCP server in PolicyLayer and add a rule for boot_sim: 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 Sl Test. Nothing to install.

What risk level is boot_sim? +

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

Can I rate-limit boot_sim? +

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

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

boot_sim is provided by the Sl Test MCP server (sampsonky/xcodebuildmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.