list_gems

THE RISK

Low Risk

Why list_gems needs a policy

This tool queries and returns information about gems (packages/modules) registered in the O3DE environment. It performs no modifications, deletions, code execution, or financial operations. The action is purely informational—reading a list of installed components.

From the tool's definition Tool name 'list_gems' and description 'List all external gems registered on this machine' indicate a retrieval operation with no side effects.

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

POLICY

How to control list_gems

PolicyLayer is an MCP gateway — it sits between your AI agents and O3de, and nothing reaches the server without passing your rules. This is the rule we recommend for list_gems:

policy.json

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

list_gems 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 O3de — 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 O3de tools

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All 30 O3de tools →

Read tools on other servers

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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 list_gems

What does the list_gems tool do? +

List all external gems registered on this machine. It is categorised as a Read tool in the O3de MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on list_gems? +

Register the O3de MCP server in PolicyLayer and add a rule for list_gems: 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 O3de. Nothing to install.

What risk level is list_gems? +

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

Can I rate-limit list_gems? +

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

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

list_gems is provided by the O3de MCP server (nickschuetz/o3de-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every O3de tool call.

Start from O3de, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →