xcode_run_single_test · Xcode MCP: Risk & Policy

WHAT IT DOES

What xcode_run_single_test does on Xcode

AI agents invoke xcode_run_single_test 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_run_single_test needs a policy

This tool executes code by triggering a test method in Xcode. While tests are typically read-only in their outcomes, the act of running tests involves executing arbitrary code logic.

From the tool's definition Tool runs a single test method. Running tests is code execution that triggers external operations (test runner, build system, simulator). The description states 'Run a single test method' which is an imperative action that executes code.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

xcode_run_single_test Rate-limited

xcode_run_single_test 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_run_single_test": {
      "limits": [
        {
          "counter": "xcode_run_single_test_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_run_single_test

What does the xcode_run_single_test tool do? +

Run a single test method. 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_run_single_test? +

Register the Xcode MCP server in PolicyLayer and add a rule for xcode_run_single_test: 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_run_single_test? +

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

Can I rate-limit xcode_run_single_test? +

Yes. Add a rate_limit block to the xcode_run_single_test 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_run_single_test completely? +

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

xcode_run_single_test 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.