import_asset · Unreal MCP: Risk & Policy

WHAT IT DOES

What import_asset does on Unreal

AI agents use import_asset to create or update resources in Unreal — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Unreal environment.

WHY IT NEEDS A POLICY

Why import_asset needs a policy

This tool imports external files into the project, which creates or adds new data/assets to the project (Write category). While reversible in principle, importing assets can have significant side effects on project structure and dependencies, and could be used to inject malicious content (models, scripts, audio) into a game project.

From the tool's definition Tool description states 'Import an external file (FBX, PNG, WAV, etc.) into the project' - this creates new assets within the Unreal Engine project.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

import_asset Rate-limited

import_asset stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "import_asset": {
      "limits": [
        {
          "counter": "import_asset_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Unreal, so you can run agents against it safely.

FAQ

Questions about import_asset

What does the import_asset tool do? +

Import an external file (FBX, PNG, WAV, etc.) into the project. It is categorised as a Write tool in the Unreal MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on import_asset? +

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

What risk level is import_asset? +

import_asset is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit import_asset? +

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

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

import_asset is provided by the Unreal MCP server (sam-david/unreal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.