Intelligent visual error detection system that scans the screen for common error patterns including red notification badges, error dialog boxes, crash messages, warning symbols, and failure indicators. Uses advanced pattern recognition to identify UI elements that typically signal problems or req...
AI agents call check_for_errors to retrieve information from macOS Simulator MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool exclusively retrieves and analyzes visual data from the screen to detect error indicators. It has no side effects—no state changes, no code execution, no data modification or deletion. The function is purely observational and informational, making it a Read operation with low severity and high confidence.
From the tool's definition The tool 'scans the screen for common error patterns', 'captures screenshots', and 'returns detailed information about detected errors' without modifying, executing, or deleting anything.
Risk signalsBulk/mass operation — affects multiple targets
Documented attack patterns abuse exactly the kind of access check_for_errors gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and macOS Simulator MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for check_for_errors:
{
"version": "1",
"default": "deny",
"tools": {
"check_for_errors": {}
}
}check_for_errors is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Intelligent visual error detection system that scans the screen for common error patterns including red notification badges, error dialog boxes, crash messages, warning symbols, and failure indicators. Uses advanced pattern recognition to identify UI elements that typically signal problems or require user attention. Can scan entire screen or specific regions. Essential for automation reliability - use after critical operations to ensure they completed successfully. Returns detailed information about detected errors including their type and location. Helps prevent cascading failures in automation workflows by catching issues early. Requires screen recording permission on macOS. It is categorised as a Read tool in the macOS Simulator MCP Server MCP Server, which means it retrieves data without modifying state.
Register the macOS Simulator MCP Server MCP server in PolicyLayer and add a rule for check_for_errors: 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 macOS Simulator MCP Server. Nothing to install.
check_for_errors is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the check_for_errors 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.
Set action: deny in the PolicyLayer policy for check_for_errors. 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.
check_for_errors is provided by the macOS Simulator MCP Server MCP server (ohqay/mac-commander). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from macOS Simulator MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
28 macOS Simulator MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.