sim_list

THE RISK

Low Risk

Why sim_list needs a policy

This tool performs data retrieval only (listing simulators) with no side effects, state changes, or destructive operations. It gathers information about available iOS simulator devices for observation purposes, which is characteristic of Read category tools.

From the tool's definition Tool description states 'List iOS simulators on the Mac' which retrieves and queries simulator information without modifying or deleting anything. The underlying command 'xcrun simctl list devices --json' is a read-only enumeration.

Documented attack patterns abuse exactly the kind of access sim_list gives an agent:

POLICY

How to control sim_list

PolicyLayer is an MCP gateway — it sits between your AI agents and Claude Pascal MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for sim_list:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "sim_list": {}
  }
}

sim_list is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Claude Pascal MCP Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Claude Pascal MCP Server tools

Destructive paserver_remove paserver_remove Destructive sim_uninstall Uninstall an app from a simulator. Destructive sim_shutdown Shut down a simulator. Pass udid='booted' to stop all running ones. Destructive sim_terminate Terminate a running app by bundle identifier. Execute adb_launch_app adb_launch_app Execute adb_stop_app Force-stop an app on the Android device. Execute build_dproj build_dproj Execute compile_delphi_project compile_delphi_project

All 53 Claude Pascal MCP Server tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about sim_list

What does the sim_list tool do? +

List iOS simulators on the Mac (xcrun simctl list devices --json). It is categorised as a Read tool in the Claude Pascal MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on sim_list? +

Register the Claude Pascal MCP Server MCP server in PolicyLayer and add a rule for sim_list: 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 Claude Pascal MCP Server. Nothing to install.

What risk level is sim_list? +

sim_list is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit sim_list? +

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

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

sim_list is provided by the Claude Pascal MCP Server MCP server (tina4stack/claude-pascal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Claude Pascal MCP Server tool call.

Start from Claude Pascal MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →